The Cincinnati Masters or Cincinnati Open (currently sponsored by the Western & Southern Financial Group) is an annual outdoor hardcourt tennis event held in the Cincinnati suburb of Mason, Ohio, USA. The event started on September 18, 1899 and is the oldest tennis tournament in the United States played in its original city.

The event is the biggest summer tennis event in the U.S., as its men's portion is one of nine elite Masters 1000 tournaments on the ATP World Tour and its women's event is one of five Premier 5 events on the WTA Tour. The 2012 event will be held August 11–19. Due to its sponsorship by the Western & Southern Financial Group, the official name of the event is the Western & Southern Open.

The tournament was started in 1899 as the Cincinnati Open (it would later be known by several other names, including the Tri-State Tennis Tournament and ATP Championships), and would eventually grow into the tournament now held in Mason. The original tournament was held at the Avondale Athletic Club, which sat on property that is now Xavier University, and would later be moved to several various locations due to changes in tournament management and surfaces. The first tournament in 1899 was played on clay courts (described in a newspaper article of the time as "crushed brick dust"), and the event was mostly played on clay until 1979 when it switched permanently to hardcourts.

Cincinnati (pronounced /sɪnsɨˈnæti/) is a city in and the county seat of Hamilton County, Ohio, United States. Settled in 1788, the city is located north of the Ohio River at the Ohio-Kentucky border, near Indiana. The population within city limits was 296,943 according to the 2010 census, making it Ohio's third-largest city. According to the 2011 Census Bureau estimate, the Cincinnati metropolitan area had a population of 2,138,038, the 27th most populous Metropolitan Statistical Area (MSA) in the United States, and the most populous in Ohio. Residents of Cincinnati are called Cincinnatians.

In the early 19th century, Cincinnati was the first American boomtown in the heart of the country to rival the larger coastal cities in size and wealth. As the first major inland city in the country, it is sometimes thought of as the first purely American city. It developed initially without as much recent European immigration or influence as took place in eastern cities. However, by the end of the 19th century, with the shift from steamboats to railroads, Cincinnati's growth had slowed considerably and the city became surpassed in population and prominence by another inland city, Chicago.

Maria Yuryevna Sharapova (Russian: Мария Юрьевна Шарапова [mɐˈrʲijə ˈjurʲjɪvnə ʂɐˈrapəvə] ( listen), US: /ʃɑrəˈpoʊvə/, UK: /ʃærəˈpoʊvə/; born April 19, 1987) is a Russian professional tennis player and former world no. 1. A United States resident since 1994, Sharapova has won 26 WTA singles titles, including three Grand Slam singles titles at the 2004 Wimbledon, 2006 US Open and 2008 Australian Open. She has also won the year-end WTA Tour Championships in 2004. The Women's Tennis Association has ranked Sharapova world no. 1 in singles on four separate occasions. She became the world no. 1 for the first time on August 22, 2005, and last regained the ranking for the fourth time on May 19, 2008. As of May 28, 2012, Sharapova is ranked world no. 2. She has been in six Grand Slam finals with the final record 3–3.

Sharapova made her professional breakthrough in 2004 at age 17, when she defeated two-time defending champion and top seed Serena Williams in the 2004 Wimbledon final for her first Grand Slam singles title. She entered the top 10 of the WTA Rankings with the win. Despite not winning a major in 2005, Sharapova briefly held the no. 1 ranking, and reached three Grand Slam semifinals, losing to the eventual champion each time. She won her second major at the 2006 US Open defeating then-world no. 1 Amélie Mauresmo in the semifinals and world no. 2 Justine Henin in the final.

Roger Federer (German pronunciation: [ˈfeːdəʁɐ]) (born 8 August 1981) is a Swiss professional tennis player who held the ATP No. 1 position for a record 237 consecutive weeks from 2 February 2004 to 18 August 2008. Federer has occupied the #1 ranking for 285 overall weeks, one week short of the record 286 weeks held by Pete Sampras. As of 28 May 2012, he is ranked World No. 3. Federer has won a men's record 16 Grand Slam singles titles. He is one of seven male players to capture the career Grand Slam and one of three (with Andre Agassi and Rafael Nadal) to do so on three different surfaces (clay, grass, and hard courts). He is the only male player in tennis history to have reached the title match of each Grand Slam tournament at least five times and also the final at each of the nine ATP Masters 1000 Tournaments. Many sports analysts, tennis critics, and former and current players consider Federer to be the greatest tennis player of all time.

Federer has appeared in an unprecedented 23 career Grand Slam tournament finals, including a men's record ten in a row, and appeared in 18 of 19 finals from the 2005 Wimbledon Championships through the 2010 Australian Open, the lone exception being the 2008 Australian Open. He holds the record of reaching the semifinals or better of 23 consecutive Grand Slam tournaments over five and a half years, from the 2004 Wimbledon Championships through the 2010 Australian Open. At the 2012 Australian Open, he reached a record 31st consecutive Grand Slam quarterfinal. During the course of his run at the 2012 French Open in Roland Garros, Federer eclipsed Jimmy Connors long standing record of 233 match wins in Grand Slam tournaments when he defeated Adrian Ungur in a second round match.

Novak Djokovic (Serbian: Новак Ђоковић or Novak Đoković; pronounced [nɔ̂ʋaːk dʑɔ̂ːkɔʋitɕ] ( listen); born 22 May 1987) is a Serbian professional tennis player who has been ranked World No. 1 by the Association of Tennis Professionals (ATP) since 4 July 2011. He has won five Grand Slam singles titles: the 2008, 2011 and 2012 Australian Open, the 2011 Wimbledon Championships, and the 2011 US Open. By winning three Majors in 2011, Djokovic became the sixth male player in the open era to win three Majors in a calendar year.

He is the first male player representing Serbia to win a Major singles title and the youngest player in the open era to have reached the semifinals of all four Grand Slam events, separately and consecutively. Amongst other titles, he won the Tennis Masters Cup in 2008 and was on the team which won the 2010 Davis Cup. He also won the bronze medal in singles at the Beijing Olympics in 2008. He has won 11 Masters 1000 series titles placing him joint fourth on the all time list. Djokovic has quickly moved up in the rankings of history. Tennis Channel ranked him number 40 , and former player Pat Cash said he is one of the greatest ever.