A light flashing approximately once per second

The second (SI unit symbol: s) is the International System of Units (SI) base unit of time^[1] and also a unit of time in other systems (abbreviated s or sec^[2]). Between 1000 (when al-Biruni used seconds) and 1960 the second was defined as 1/86,400 of a mean solar day (that definition still applies in some astronomical and legal contexts).^[3][4] Between 1960 and 1967, it was defined in terms of the period of the Earth's orbit around the Sun in 1900,^[5] but it is now defined more precisely in atomic terms. Seconds may be measured using mechanical, electric or atomic clocks.

However, 19th- and 20th-century astronomical observations revealed that this average time is lengthening and thus the sun–earth motion is no longer considered a suitable basis for definition. With the advent of atomic clocks, it became feasible to define the second based on fundamental properties of nature. Since 1967, the second has been defined to be:

the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.^[1]

SI prefixes are frequently combined with the word second to denote subdivisions of the second, e.g., the millisecond (one thousandth of a second), the microsecond (one millionth of a second), and the nanosecond (one billionth of a second). Though SI prefixes may also be used to form multiples of the second such as kilosecond (one thousand seconds), such units are rarely used in practice. The more common larger non-SI units of time are not formed by powers of ten; instead, the second is multiplied by 60 to form a minute, which is multiplied by 60 to form an hour, which is multiplied by 24 to form a day.

The second is also the base unit of time in the centimetre-gram-second, metre-kilogram-second, metre-tonne-second, and foot-pound-second systems of units.

International second[link]

Under the International System of Units (via the International Committee for Weights and Measures, or CIPM), since 1967 the second has been defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.^[1] In 1997 CIPM added that the periods would be defined for a caesium atom at rest, and approaching the theoretical temperature of absolute zero, and in 1999, it included corrections from ambient radiation.^[1]

This definition refers to a caesium atom at rest at a temperature of 0 K (absolute zero). Absolute zero implies no movement, and therefore zero external radiation effects (i.e., zero local electric and magnetic fields). The second thus defined is consistent with the ephemeris second, which was based on astronomical measurements. (See History below.)

The realization of the standard second is described briefly in a special publication from the National Institute of Standards and Technology,^[6] and in detail by the National Research Council of Canada.^[7]

Equivalence to other units of time[link]

1 international second is equal to:

• 1/60 minute (but see also leap second)
• 1/3,600 hour
• 1/86,400 day (IAU system of units)
• 1/31,557,600 Julian year (IAU system of units)

History[link]

Before mechanical clocks[link]

The Egyptians subdivided daytime and nighttime into twelve hours each since at least 2000 BC, hence the seasonal variation of their hours. The Hellenistic astronomers Hipparchus (c. 150 BC) and Ptolemy (c. AD 150) subdivided the day sexagesimally and also used a mean hour (¹⁄₂₄ day), simple fractions of an hour (¹⁄₄, ²⁄₃, etc.) and time-degrees (¹⁄₃₆₀ day or four modern minutes), but not modern minutes or seconds.^[8]

The day was subdivided sexagesimally, that is by ¹⁄₆₀, by ¹⁄₆₀ of that, by ¹⁄₆₀ of that, etc., to at least six places after the sexagesimal point (a precision of better than 2 microseconds) by the Babylonians after 300 BC. For example, six fractional sexagesimal places of a day was used in their specification of the length of the year, although they were unable to measure such a small fraction of a day in real time. As another example, they specified that the mean synodic month was 29;31,50,8,20 days (four fractional sexagesimal positions), which was repeated by Hipparchus and Ptolemy sexagesimally, and is currently the mean synodic month of the Hebrew calendar, though restated as 29 days 12 hours 793 halakim (where 1 hour = 1080 halakim).^[9] The Babylonians did not use the hour, but did use a double-hour lasting 120 modern minutes, a time-degree lasting four modern minutes, and a barleycorn lasting 3¹⁄₃ modern seconds (the helek of the modern Hebrew calendar),^[10] but did not sexagesimally subdivide these smaller units of time. No sexagesimal unit of the day was ever used as an independent unit of time.

In 1000, the Persian scholar al-Biruni gave the times of the new moons of specific weeks as a number of days, hours, minutes, seconds, thirds, and fourths after noon Sunday.^[4] In 1267, the medieval scientist Roger Bacon stated the times of full moons as a number of hours, minutes, seconds, thirds, and fourths (horae, minuta, secunda, tertia, and quarta) after noon on specified calendar dates.^[11] Although a third for ¹⁄₆₀ of a second remains in some languages, for example Polish (tercja) and Turkish (salise), the modern second is subdivided decimally.

Seconds measured by mechanical clocks[link]

The earliest clocks to display seconds appeared during the last half of the 16th century. The earliest spring-driven timepiece with a second hand which marked seconds is an unsigned clock depicting Orpheus in the Fremersdorf collection, dated between 1560 and 1570.^{[12]:417–418[13]} During the 3rd quarter of the 16th century, Taqi al-Din built a clock with marks every 1/5 minute.^[14] In 1579, Jost Bürgi built a clock for William of Hesse that marked seconds.^[12]:105 In 1581, Tycho Brahe redesigned clocks that displayed minutes at his observatory so they also displayed seconds. However, they were not yet accurate enough for seconds. In 1587, Tycho complained that his four clocks disagreed by plus or minus four seconds.^[12]:104

The second first became accurately measurable with the development of pendulum clocks keeping mean time (as opposed to the apparent time displayed by sundials). In 1644, Marin Mersenne calculated that a pendulum with a length of 39.1 inches (0.994 m) would have a period at standard gravity of precisely two seconds, one second for a swing forward and one second for the return swing, enabling such a pendulum to tick in precise seconds.

In 1670, London clockmaker William Clement added this seconds pendulum to the original pendulum clock of Christian Huygens.^[15] From 1670 to 1680, Clement made many improvements to his clock and introduced the longcase or grandfather clock to the public. This clock used an anchor escapement mechanism with a seconds pendulum to display seconds in a small subdial. This mechanism required less power, caused less friction and was accurate enough to measure seconds reliably as one-sixtieth of a minute than the older verge escapement. Within a few years, most British precision clockmakers were producing longcase clocks and other clockmakers soon followed. Thus the second could now be reliably measured.

Modern measurements[link]

In 1956 the second was defined in terms of the period of revolution of the Earth around the Sun for a particular epoch, because by then it had become recognized that the Earth's rotation on its own axis was not sufficiently uniform as a standard of time. The Earth's motion was described in Newcomb's Tables of the Sun (1895), which provide a formula estimating the motion of the Sun relative to the epoch 1900 based on astronomical observations made between 1750 and 1892.^[5] The second thus defined is

the fraction 1/31,556,925.9747 of the tropical year for 1900 January 0 at 12 hours ephemeris time.^[5]

This definition was ratified by the Eleventh General Conference on Weights and Measures in 1960. The tropical year in the definition was not measured, but calculated from a formula describing a mean tropical year that decreased linearly over time, hence the curious reference to a specific instantaneous tropical year. This definition of the second was in conformity with the ephemeris time scale adopted by the IAU in 1952,^[16] defined as the measure of time that brings the observed positions of the celestial bodies into accord with the Newtonian dynamical theories of their motion (those accepted for use during most of the 20th century being Newcomb's Tables of the Sun, used from 1900 through 1983, and Brown's Tables of the Moon, used from 1923 through 1983).^[5]

With the development of the atomic clock, it was decided to use atomic clocks as the basis of the definition of the second, rather than the revolution of the Earth around the Sun.

Following several years of work, Louis Essen from the National Physical Laboratory (Teddington, England) and William Markowitz from the United States Naval Observatory (USNO) determined the relationship between the hyperfine transition frequency of the caesium atom and the ephemeris second.^[5][17] Using a common-view measurement method based on the received signals from radio station WWV,^[18] they determined the orbital motion of the Moon about the Earth, from which the apparent motion of the Sun could be inferred, in terms of time as measured by an atomic clock. They found that the second of ephemeris time (ET) had the duration of 9,192,631,770 ± 20 cycles of the chosen caesium frequency.^[17] As a result, in 1967 the Thirteenth General Conference on Weights and Measures defined the second of atomic time in the International System of Units as

FOCS 1, a continuous cold caesium fountain atomic clock in Switzerland, started operating in 2004 at an uncertainty of one second in 30 million years.

the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom.^[5]

This SI second, referred to atomic time, was later verified to be in agreement, within 1 part in 10¹⁰, with the second of ephemeris time as determined from lunar observations.^[19] (Nevertheless, this SI second was already, when adopted, a little shorter than the then-current value of the second of mean solar time.^[20][21])

During the 1970s it was realized that gravitational time dilation caused the second produced by each atomic clock to differ depending on its altitude. A uniform second was produced by correcting the output of each atomic clock to mean sea level (the rotating geoid), lengthening the second by about 1×10⁻¹⁰. This correction was applied at the beginning of 1977 and formalized in 1980. In relativistic terms, the SI second is defined as the proper time on the rotating geoid.^[22]

The definition of the second was later refined at the 1997 meeting of the BIPM to include the statement

This definition refers to a caesium atom at rest at a temperature of 0 K.

The revised definition seems to imply that the ideal atomic clock contains a single caesium atom at rest emitting a single frequency. In practice, however, the definition means that high-precision realizations of the second should compensate for the effects of the ambient temperature (black-body radiation) within which atomic clocks operate, and extrapolate accordingly to the value of the second at a temperature of absolute zero.

Today, the atomic clock operating in the microwave region is challenged by atomic clocks operating in the optical region. To quote Ludlow et al.,^[23] “In recent years, optical atomic clocks have become increasingly competitive in performance with their microwave counterparts. The overall accuracy of single trapped ion based optical standards closely approaches that of the state-of-the-art caesium fountain standards. Large ensembles of ultracold alkaline earth atoms have provided impressive clock stability for short averaging times, surpassing that of single-ion based systems. So far, interrogation of neutral atom based optical standards has been carried out primarily in free space, unavoidably including atomic motional effects that typically limit the overall system accuracy. An alternative approach is to explore the ultranarrow optical transitions of atoms held in an optical lattice. The atoms are tightly localized so that Doppler and photon-recoil related effects on the transition frequency are eliminated.”

The NRC attaches a "relative uncertainty" of 2.5×10⁻¹¹ (limited by day-to-day and device-to-device reproducibility) to their atomic clock based upon the ¹²⁷I₂ molecule, and is advocating use of an ⁸⁸Sr ion trap instead (relative uncertainty due to linewidth of 2.2×10⁻¹⁵). See magneto-optical trap and "Trapped ion optical frequency standards". National Physical Laboratory. http://www.npl.co.uk/server.php?show=ConWebDoc.1086.  Such uncertainties rival that of the NIST F-1 caesium atomic clock in the microwave region, estimated as a few parts in 10¹⁶ averaged over a day.^[24][25]

SI multiples[link]

SI prefixes are commonly used to measure time less than a second, but rarely for multiples of a second (which is known as metric time). Instead, the non-SI units minutes, hours, days, Julian years, Julian centuries, and Julian millennia are used.

Other current definitions[link]

For specialized purposes, a second may be used as a unit of time in time scales where the precise length differs slightly from the SI definition. One such time scale is UT1, a form of universal time. McCarthy and Seidelmann refrain from stating that the SI second is the legal standard for timekeeping throughout the world, saying only that "over the years UTC [which ticks SI seconds] has become either the basis for legal time of many countries, or accepted as the de facto basis for standard civil time".^[26]

See also[link]

• Atomic clock
• Becquerel
• Coordinated Universal Time
• Hertz
• International Atomic Time
• International System of Units
• Leap second
• Magneto-optical trap
• Time standard

References[link]

External links[link]

Look up second in Wiktionary, the free dictionary.

Wikimedia Commons has media related to: Second

• National Physical Laboratory: Trapped ion optical frequency standards
• High-accuracy strontium ion optical clock; National Physical Laboratory (2005)
• National Research Council of Canada: Optical frequency standard based on a single trapped ion
• NIST: Definition of the second; notice the cesium atom must be in its ground state at 0 K
• Official BIPM definition of the second
• Seconds and leap seconds by the USNO
• The leap second: its history and possible future
• What is a Cesium atom clock?

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Lionel Messi

Messi playing for Barcelona
Personal information
Full name	Lionel Andrés Messi[1]
Date of birth	(1987-06-24) 24 June 1987 (age 25)[1]
Place of birth	Rosario, Argentina[1]
Height	1.69 m (5 ft 7 in)[1]
Playing position	Forward
Club information
Current club	Barcelona
Number	10
Youth career
1995–2000	Newell's Old Boys
2000–2003	Barcelona
Senior career*
Years	Team	Apps†	(Gls)†
2003–2004	Barcelona C	8	(5)
2004–2005	Barcelona B	22	(6)
2004–	Barcelona	214	(169)
National team‡
2005	Argentina U20	16	(11)
2008	Argentina U23	5	(2)
2005–	Argentina	68	(22)
Honours Competitor for  Argentina Men's Football Gold 2008 Beijing Team Competition
* Senior club appearances and goals counted for the domestic league only and correct as of 22:30, 13 May 2012 (UTC). † Appearances (Goals). ‡ National team caps and goals correct as of 19:30, 24 March 2012 (UTC)

Lionel Andrés Messi (Spanish pronunciation: [ljoˈnel anˈdɾes ˈmesi], born 24 June 1987) is an Argentine footballer who plays in La Liga for FC Barcelona and is the captain of the Argentina national team, mainly as a forward.

By the age of 21, Messi had received Ballon d'Or and FIFA World Player of the Year nominations. The following year in 2009 he won both the Ballon d'Or^[2] and FIFA World Player of the Year, and won the inaugural FIFA Ballon d'Or in 2010 and 2011.^[3] He also won the 2010–11 UEFA Best Player in Europe Award. Messi is the fourth football player to win three Ballons d'Or, after Johan Cruyff, Michel Platini and Marco van Basten and the second player to win three consecutive Ballons d'Or, after Michel Platini. His playing style and small stature have drawn comparisons to Diego Maradona, who himself declared Messi as his "successor".^[4][5]

Messi has won five La Liga titles and three Champions League titles. In 2012, Messi made UEFA Champions League history by becoming the first player to score five goals in one match, in a 7–1 win against Bayer Leverkusen.^[6] With two goals in the next round against A.C. Milan, he matched José Altafini's record of 14 goals in a single UEFA Champions League/European Cup season.^[7] He also became the first player to top-score in four successive European Champion Clubs' Cup campaigns.^[8][9] He set the world record for most goals scored in a season during the 2011–12 season, with 73 goals.^[10]

Messi was the top scorer of the 2005 FIFA World Youth Championship with six goals. In 2006, he became the youngest Argentine to play in the FIFA World Cup and he won a runners-up medal at the Copa América tournament the following year. In 2008, he won his first international honour, an Olympic gold medal, with the Argentina Olympic football team.

Early life[link]

Messi was born in Rosario, Santa Fe Province, to parents Jorge Horacio Messi, a factory steel worker, and Celia María Cuccittini, a part-time cleaner.^{[11][12][13][14]} His paternal family originates from the Italian city of Ancona, from which his ancestor, Angelo Messi, emigrated to Argentina in 1883.^[15][16] He has two older brothers, Rodrigo and Matías, and a sister, María Sol.^[17] At the age of five, Messi started playing football for Grandoli, a local club coached by his father Jorge.^[18] In 1995, Messi switched to Newell's Old Boys who were based in his home city Rosario.^[18] At the age of 11, he was diagnosed with a growth hormone deficiency.^[19] Local powerhouse River Plate showed interest in Messi's progress, but did not have enough money to pay for treatment for his condition, which cost $900 a month.^[14] Carles Rexach, the sporting director of FC Barcelona, had been made aware of his talent as Messi had relatives in Lleida, Catalonia, and Messi and his father were able to arrange a trial with the team.^[14] Rexach, with no other paper at hand, offered Messi a contract written on a paper napkin.^[20][21] Barcelona offered to pay for Messi's medical bills if he was willing to move to Spain. Messi and his father moved to Barcelona where Messi enrolled in the club's youth academy.^[18][21]

Club career[link]

Barcelona[link]

Messi played in Barcelona's junior Infantil B and Cadete B & A teams from 2000 to 2003 (scoring 37 goals in 30 matches in Cadete A). Season 2003–04 saw him on a record^[22] five different teams: He started one match in Juvenil B (one goal) and got promoted to Juvenil A (14 matches, 21 goals). Later he debuted for FC Barcelona C team (Tercera División) on 29 November 2003 and for FC Barcelona B (Segunda División B) on 6 March 2004. He played for both teams during the season (eight matches, five goals and five games, zero goals, respectively).^[23][24][25] Even before these two debuts, Messi made his official debut for the first-team on 16 November 2003 aged 16 years and 145 days, in a friendly match against Porto.^[26][27]

Less than a year after his start, Frank Rijkaard gave him his league debut against RCD Espanyol on 16 October 2004 (at 17 years and 114 days), becoming the third-youngest player ever to play for Barcelona and youngest club player who played in La Liga, which would be broken by Bojan Krkić in September 2007. When he scored his first senior goal for the club against Albacete Balompié on 1 May 2005, Messi was 17 years, ten months and seven days old, becoming the youngest to ever score in a La Liga game for Barcelona^[28] until it was again broken by Bojan Krkić in 2007, scoring from a Messi assist.^[29] Messi said about his ex-coach Rijkaard: "I'll never forget the fact that he launched my career, that he had confidence in me while I was only sixteen or seventeen."^[30] During the season, Messi played also in Barcelona B (Segunda División B) scoring 6 goals in 17 matches.

2005–06 season[link]

On 16 September, for the second time in three months, Barcelona announced an update to Messi's contract; this time it was improved to pay him as a first team member and extended until June 2014.^[18] Messi obtained Spanish citizenship on 26 September 2005^[31] and was finally able to make his debut in the season's Spanish First Division. Messi's first home outing in the Champions League came on 27 September against Italian club Udinese.^[26] Fans at Barcelona's stadium, the Camp Nou, gave Messi a standing ovation upon his substitution, as his composure on the ball and passing combinations with Ronaldinho had paid dividends for Barcelona.^[32]

Messi netted six goals in 17 league appearances, and scored one Champions League goal in six. His season ended prematurely on 7 March 2006, however, when he suffered a muscle tear in his right thigh during the second leg of the second round Champions League tie against Chelsea.^[33] Rijkaard's Barcelona ended the season as champions of Spain and Europe.^[34][35]

2006–07 season[link]

Messi in a match against Rangers in 2007

In the 2006–07 season, Messi established himself as a regular first team player, scoring 14 times in 26 matches.^[36] On 12 November, in the game against Real Zaragoza, Messi suffered a broken metatarsal, ruling him out for three months.^[37][38] On 11 March, El Clásico saw Messi in top form, scoring a hat-trick to earn 10-man Barcelona a 3–3 draw, equalising three times, with the final equaliser coming in injury time.^[39] In doing so he became the first player since Iván Zamorano (for Real Madrid in the 1994–95 season) to score a hat-trick in El Clásico.^[40] Messi is also the youngest player ever to have scored in this fixture. Towards the end of the season he began finding the net more often; 11 of his 14 league goals for the season came from the last 13 games.^[41]

Messi shortly before scoring a goal against Getafe

Messi also proved the "new Maradona" tag was not all hype, by nearly replicating Maradona's most famous goals in the space of the single season.^[42] On 18 April 2007, he scored two goals during a Copa del Rey semi-final against Getafe CF, one of which was very similar to Maradona's famous goal against England at the 1986 World Cup in Mexico, known as the Goal of the Century.^[43] The world's sports press drew comparisons with Maradona, and the Spanish press labelled Messi as "Messidona".^[44] He ran about the same distance, 62 metres (203 ft), beat the same number of players (six, including the goalkeeper), scored from a very similar position, and ran towards the corner flag just as Maradona did in Mexico 21 years before.^[42] In a press conference after the game, Messi's team-mate Deco said: "It was the best goal I have ever seen in my life."^[45] Against RCD Espanyol Messi also scored a goal which was remarkably similar to Maradona's 'Hand of God' goal against England in the World Cup quarter-finals. Messi launched himself at the ball and connected with his hand to guide the ball past the goalkeeper Carlos Kameni.^[46] Despite protests by Espanyol players and replays showing it was clear handball, the goal stood.^[46]

2007–08 season[link]

Messi takes Barcelona to 2–0 against Sevilla at Camp Nou on 22 September 2007

On 27 February, Messi played in his 100th official match for Barcelona against Valencia.^[47]

Messi was nominated for a FIFPro World XI Player Award under the category of Forward.^[48] A poll conducted in the online edition of the Spanish newspaper Marca had him as the best player in the world with 77 percent of the vote.^[49] Columnists from Barcelona-based newspapers El Mundo Deportivo and Sport stated that the Ballon d'Or should be given to Messi, a view supported by Franz Beckenbauer.^[50] Football personalities such as Francesco Totti have declared that they consider Messi to be one of the current best footballers in the world.^[51]

Messi was sidelined for six weeks following an injury on 4 March when he suffered a muscle tear in his left thigh during a Champions League match against Celtic. It was the fourth time in three seasons that Messi suffered this type of injury.^[52] When the season was over Messi managed to score 16 goals and assisted 13 times in all competition.

2008–09 season[link]

Upon Ronaldinho's departure from the club, Messi inherited his number 10 jersey.^[53] During this season he placed second in the 2008 FIFA World Player of the Year awards with 678 points.

Michael Carrick defending a shot from Messi in the 2009 UEFA Champions League Final

Messi scored his first hat-trick of 2009 in a Copa del Rey tie against Atlético Madrid which Barcelona won 3–1.^[54] Messi scored another important double on 1 February 2009, coming on as a second half substitute to help Barcelona defeat Racing Santander 1–2 after being 1–0 down. The second of the two strikes was Barcelona's 5000th league goal.^[55] On 8 April 2009, he scored twice against Bayern Munich in the Champions League, setting a personal record of eight goals in the competition.^[56]

As Barcelona's season was drawing to a close, Messi scored twice (his 35th and 36th goals in all competitions) to cap a 6–2 win over Real Madrid at the Santiago Bernabéu^[57] in what was Real's heaviest defeat since 1930.^[58] He won his first Copa del Rey on 13 May, scoring one goal and assisting another two, in a 4–1 victory over Athletic Bilbao.^[59] He helped his team win the double by winning La Liga. On 27 May he helped Barcelona win the Champions League by scoring a second goal in the 70th minute giving Barcelona a two goal lead; he also became the top scorer in the Champions League, the youngest in the tournament's history, with nine goals.^[60] Messi also won the UEFA Club Forward of the Year: and the UEFA Club Footballer of the Year rounding off a spectacular year in Europe.^[61] This victory meant Barcelona had won the Copa del Rey, La Liga and Champions League in the one season,^[62] and was the first time a Spanish club had ever won the treble.^[63]

2009–10 season[link]

After winning the 2009 UEFA Super Cup, Barcelona manager Josep Guardiola asserted that Messi was probably the best player he had ever seen.^[65] On 18 September, Messi signed a new contract with Barcelona, running until 2016 and with a buy-out clause of €250 million included, making Messi, along with Zlatan Ibrahimović, the highest paid players in La Liga, with earnings of around €9.5 million yearly.^[66][67]

Messi was named winner of the 2009 Ballon d'Or on 1 December 2009, beating runner-up Cristiano Ronaldo by largest ever margin of 473 to 233.^[68][69][70]

Messi at the 2009 FIFA Club World Cup

On 19 December, Messi scored the winner in the final of the 2009 Club World Cup against Estudiantes in Abu Dhabi, giving the club their sixth title of the year.^[71] Two days later, he was given the FIFA World Player of the Year award,^[72] beating Cristiano Ronaldo, Xavi, Kaká and Andrés Iniesta to the award. This was the first time he had won the award, and he became the first Argentinian to ever receive this honour.^[73] On 10 January 2010, Messi scored his first hat-trick in 2010 and his first hat-trick of the season against CD Tenerife in the 0–5 victory,^[74] and on 17 January he scored his 100th goal for the club in the 4–0 victory over Sevilla.^[75]

Messi scored a hat-trick against Valencia CF in a 3–0 home win,^[76] and finally he scored another hat-trick against Zaragoza in a 4–2 away win,^[77] becoming the first Barcelona player to score back-to-back hat-tricks in La Liga.^[78] He played his 200th official match for Barcelona against Osasuna on 24 March 2010.^[79]

On 6 April 2010, for the first time in Messi's career he scored four goals in a single match, netting the lot in a 4–1 home win over Arsenal in the Champions League quarter-final second leg.^[82][83] This also saw him overtake Rivaldo as Barcelona's all time greatest scorer in the competition.^[84] In the final league match of the season against Valladolid, he scored two goals in the second half to tie Ronaldo's club record of 34 goals in a single league season, set in 1996–97,^[85][86] and to finish four goals behind the all-time record held by Telmo Zarra.^[87] He was named La Liga player of the year for the second year in a row on 3 June 2010.^[88]

2010–11 season[link]

On 21 August 2010, Messi scored a hat-trick in his first start of the season in a 4–0 victory over Sevilla FC in the Supercopa de España, helping Barcelona secure their first trophy of the season after a 1–3 first leg loss.^[89]

On 19 September 2010, Messi suffered an ankle injury due to an ill-advised tackle by Atlético Madrid defender Tomáš Ujfaluši in the 92nd minute of their Round 3 match at the Vicente Calderón Stadium. At first sight it was feared that Messi suffered a broken ankle that could have kept the star player away from the pitch for a minimum of six months, but MRI performed the next day in Barcelona showed he suffered a sprain in the internal and external ligaments of his right ankle.^[90] Team-mate David Villa stated "the tackle on Messi was brutal" after watching the video of the play and also added that he believed the Atlético defender "didn't go into the tackle to hurt".^[91] The incident caused widespread media attention and brought up the debate of equality in protecting all players in the game.

Against Almería Messi scored his second hat-trick of the season in an impressive 8–0 away win, the second of which was his 100th La Liga goal.^[92]

Messi playing against Real Madrid in a Champions League match

Messi won the 2010 FIFA Ballon d'Or, beating his Barcelona teammates Xavi and Iniesta.^[93] Messi had been nominated for the awards for the fourth consecutive year.^[94] On 5 February, Barcelona broke the record for most consecutive league wins with 16 victories after they defeated Atlético Madrid 3–0 at the Camp Nou.^[95] Lionel Messi scored a hat-trick to ensure the victory for his side and after the match he stated, "it's an honor to be able to pass a record set by a great like Di Stéfano" and "if the record has been around for so long is because it's very complicated to achieve and we have reached it by defeating a very difficult team who's going through a bad situation, which makes it even more difficult."^[96]

After failing to score for a month he scored a brace against UD Almería; the second goal was his 47th of the season, equalling his club record return of the previous season.^[97] He surpassed his record on 12 April 2011 by scoring the winner against Shakhtar Donetsk in a UEFA Champions League game, which put him in the record book as all time top scorer in a single season for Barcelona.^[98] He scored his eighth goal on El Clásico on a 1–1 tie at the Santiago Bernabéu Stadium. On 23 April, Messi scored his 50th goal of the season against CA Osasuna in a 2–0 home victory which he came on as a substitute in the 60th minute.^[99] He finished the season by winning La Liga and scoring 31 goals.

On 20 April, Barcelona were defeated by arch-rivals Real Madrid in the 2011 Copa del Rey Final. Messi set up a goal for Pedro, which was however ruled offside. Cristiano Ronaldo scored the only goal of the match in extra time. Messi was however the joint top-scorer of the tournament along with Cristiano Ronaldo, with 7 goals.^{[100] [101][101]}

In the first leg of the Champions League semi-finals, he gave a memorable performance, scoring twice against Real Madrid in a 2–0 win, the second goal (a dribble past several players) being acclaimed as one of the best ever at that stage of the competition.^[102][103] At the Champions League Final at Wembley, Messi scored the eventual game-clinching goal to give Barcelona their third title in six years and fourth overall.^[104] This was also Messi's 12th goal in the Champions League that season, which allowed him to tie Ruud Van Nistelrooy's record of 12 goals in a single European Cup season, after it was re-established as the UEFA Champions League, in 1992.^[101] The overall record of goals scored in a single European Cup Season, is José Altafini's record of 14 goals, which Messi did however equal in the following season.^[101] Messi finished the 2010-11 season with 53 goals in all competitions.

2011–12 season[link]

Messi started the season by lifting the Spanish Supercup with Barcelona, scoring three goals and providing two assists in a 5–4 aggregate win against Real Madrid.^[105] His vital interventions continued in the next official match played against Porto when he scored again following a weak back pass from Fredy Guarín before setting up Cesc Fàbregas to give Barcelona a 2–0 victory and the UEFA Super Cup,^[106] then the only official competition that remained for him to score in.^[107]

After scoring his first goal of an eventual hat-trick in an 8–0 rout against Osasuna, Messi produced a special celebration for Soufian, a 10-year-old Moroccan boy with Laurin Sandrow syndrome, a rare medical condition that can eventually lead to the loss of the lower extremities. Whilst Messi usually points to the sky after scoring a goal, Messi slapped his thighs as a dedication to Soufian.^[108]

In August, Messi became the second highest goalscorer surpassing László Kubala on 194 goals, being behind only to César Rodríguez on 232 goals in all official competitions.^[109]

On 28 September, Messi scored his first two Champions League goals of the season against BATE Borisov,^[110] becoming Barcelona's second highest goalscorer in its history, tying László Kubala, at 194 goals in all official competitions.^[111] He surpassed that record when he scored two goals against Racing Santander.^[112] He became second in Barcelona's La Liga goalscorers list with 132 goals, one more than Kubala.^[113] He scored his 200th Barcelona goal and two more as part of a hat-trick in his next game against Viktoria Plzeň in the Champions League.^[114]

Messi scored a brace in the Club World Cup Final against Santos and was recognized as the man of the match and also awarded the Golden Ball for his performance during the tournament.^[115]

Messi won the 2011 UEFA Best Player in Europe Award, beating his Barcelona team-mate Xavi Hernández and Real Madrid's Cristiano Ronaldo. Messi won the 2011 FIFA Ballon d'Or, again beating his team-mate Xavi and Cristiano Ronaldo. By winning the FIFA Ballon d'Or again, Messi become the fourth player to win three Ballon d'Ors, after Johan Cruyff, Michel Platini and Marco Van Basten and the second player to win three consecutive Ballon d'Ors, after Michel Platini (although two of his Ballon d'Ors are FIFA Ballon d'Ors, which he won consecutively).

On 19 February 2012, Messi, on his 200th La Liga appearance, scored four goals against Valencia in a 5–1 win.^[116] On 7 March, Messi became the first player to score five goals in an UEFA Champions League match since the tournament's re-establishment in 1992, helping the defending champions Barcelona win 7–1 against Bayer Leverkusen.^[117]

On 20 March, Messi scored three goals against Granada, making him FC Barcelona's leading goalscorer in official competitions, surpassing club legend César Rodríguez, who had previously held the record with 232.^[118]

On 3 April, Messi scored two goals from penalty kicks against Milan in the second leg of the Champions League Quarter-final, allowing him to surpass his personal record, joint with Ruud van Nistelrooy, of 12 goals in a single UEFA Champions League season. These goals allowed him to tie José Altafini's record of 14 goals in a single European Cup season in the 1962–63 season, before the tournament's re-establishment as the UEFA Champions League in 1992.^[101] Barcelona were knocked out in the semi-finals to eventual winners Chelsea.

On 11 April, Messi scored his 61th goal against Getafe, surpassing Isidro Langara's record of 60 goals in 1933–34, and became the best goalscorer in history in one season in Spain.^{[citation needed]}

On 2 May, Messi scored a hat-trick against Málaga surpassing Gerd Müller's record (67 goals in 1972-73) with 68 goals, and thus becoming the best goalscorer in history in one season in Europe.^[119] It was the 21st multi-goal game of the season for Messi and his seventh La Liga hat-trick.^[120] He then scored four goals on 5 May against Espanyol to take his tally to an unprecedented 72 goals, in the process becoming only the second player to pass 70 goals in a first division season since Archie Stark of Bethlehem Steel in the American Soccer League in 1924–25.^[121]

On 25 May, he scored again in the 2012 Copa del Rey Final, helping Barcelona win their 26th Spanish Cup title, and increasing his seasonal goalscoring record to an unmatched 73 goals in all competitions.^{[122] [123]} This was also Guardiola's last match as Barcelona's manager, and the Cup win marked Messi's second Copa del Rey title, after losing the final the year before, as well as his 14th Barcelona trophy during Guardiola's 4 seasons at the club. Although Barcelona failed to win their 4th consecutive Liga title under Guardiola, finishing runners up to arch-rivals Real Madrid, Messi finished the 2011–12 season as the top goalscorer in La Liga for a second time, with a Liga record of 50 goals. He also ended the season as the UEFA Champions' League Top Scorer for a fourth consecutive time, with 14 goals.^[124]

International career[link]

Often referred to as an Argentinian-Spanish player, this crossover was brought into sharp focus when in 2004, Lionel was offered the chance to play for the Spanish national U-20 team. He declined the offer given his Argentinian heritage, and was given the opportunity to play for Argentina's U-20 team in a friendly match against Paraguay in June 2004.^[125] In 2005 he was part of a team that finished 3rd in 2005 South American Youth Championship in Colombia. He won the 2005 FIFA World Youth Championship in the Netherlands with the team and won the Golden Ball and the Golden Shoe,^[126] scoring in the last four of Argentina's matches and netting a total of six for the tournament.

He made his full international debut on 17 August 2005 against Hungary at the age of 18. He was substituted on during the 63rd minute, but was sent off on the 65th minute because the referee, Markus Merk, claimed that Messi had allegedly elbowed defender Vilmos Vanczák, who was tugging Messi's shirt. The decision was contentious and Maradona even claimed the decision was pre-meditated. Messi was later reportedly found weeping in the changing rooms after the decision.^[127][128] Messi returned to the team on 3 September in Argentina's 1–0 World Cup qualifier away defeat to Paraguay. Ahead of the match he had said "This is a re-debut. The first one was a bit short."^[129] He then started his first game for Argentina against Peru, in which he was able to win a crucial penalty for Argentina; after the match Pekerman described Messi as "a jewel".^[130]

On 28 March 2009, in a World Cup Qualifier against Venezuela, Messi wore the number 10 jersey for the first time with Argentina. This match was the first official match for Diego Maradona as the Argentina manager. Argentina won the match 4–0 with Messi opening the scoring.^[131]

On 17 November 2010, Messi scored a last-minute goal against South American rivals Brazil after an individual effort to help his team to a 1–0 win in the friendly match, which was held in Doha. This was the first time that he had scored against Brazil at senior level.^[132] Messi scored another last-minute goal on 9 February 2011 against Portugal in a penalty kick which gave his side a 2–1 victory in the friendly match, which was held in Geneva, Switzerland.^[133] His first hat-trick for Albiceleste came against Switzerland, on 29 February 2012 which the game ended 3–1 for Argentina.^[134]

2006 World Cup[link]

The injury that kept Messi from playing for two months at the end of the 2005–06 season jeopardised his presence in the 2006 World Cup. Nevertheless, Messi was selected in the Argentina squad for the tournament on 15 May 2006. He also played in the final match before the World Cup against the Argentine U-20 team for 15 minutes and a friendly match against Angola from the 64th minute.^[135][136] He witnessed Argentina's opening match victory against Ivory Coast from the substitute's bench.^[137] In the next match against Serbia and Montenegro, Messi became the youngest player to represent Argentina at a World Cup when he came on as a substitute for Maxi Rodríguez in the 74th minute. He assisted Hernán Crespo's goal within minutes of entering the game and also scored the final goal in the 6–0 victory, making him the youngest scorer in the tournament and the sixth youngest goalscorer in the history of the World Cup.^[138] Messi started in Argentina's following 0–0 draw against the Netherlands.^[139] In the following game against Mexico, Messi came on as a substitute in the 84th minute, with the score tied at 1–1. He appeared to score a goal, but it was ruled offside with Argentina needing a late goal in extra time to proceed.^[140][141] Coach José Pekerman left Messi on the bench during the quarter-final match against Germany, which they lost 4–2 on a penalty shootout.^[142]