Justine Henin (French pronunciation: [ʒys.tin enɛ̃]; born 1 June 1982), known as Justine Henin-Hardenne between 2002 and 2007, is a retired professional Belgian tennis player and former World No. 1.

Henin won 43 WTA singles titles and seven Grand Slam singles titles, including four French Open titles, one Australian Open title, and two US Open titles. She has also won the year-ending Sony Ericsson Championships twice and the singles gold medal at the 2004 Summer Olympics.

Tennis experts cite her mental toughness, the completeness and variety of her game, her footspeed and footwork, and her one-handed backhand (which John McEnroe has described as the best single-handed backhand in the women's or men's game) as the principal reasons for her success.

Critics and all-time-great players have made testament to Henin's talent. Upon Henin's first retirement from the WTA in the early part of the 2008 season, Billie Jean King said that "pound for pound, Henin is the best tennis player of her generation", as well as that "Justine is the best women's athlete I've ever seen."Andre Agassi said of Henin, "Justine Henin is one of the most talented women ever to have played the game of tennis." In 2007, 18 time Grand Slam winner Martina Navratilova said that "She is head and shoulders above everyone else right now." John McEnroe concurred, saying that Henin is "The player I most like to watch." Henin made a return to the WTA in early 2010, losing the final of the Australian Open in only her 2nd tournament back.

Serena Jameka Williams (born September 26, 1981) is an American professional tennis player and a former world no. 1. The Women's Tennis Association has ranked her world no. 1 in singles on five separate occasions. She became the world no. 1 for the first time on July 8, 2002 and regained this ranking for the fifth time on November 2, 2009. She is the only female player to have won over $35 million in prize money.

Her 27 Grand Slam titles places her ninth on the all-time list: 13 in singles, 12 in women's doubles, and 2 in mixed doubles. She is the most recent player, male or female, to have held all four Grand Slam singles titles simultaneously and only the fifth woman in history to do so. She was also the first woman, along with sister Venus Williams, to hold all four Grand Slam doubles titles simultaneously since Martina Hingis did so in 1998. Her 13 Grand Slam singles titles is sixth on the all-time list. Williams ranks fourth in Grand Slam women's singles titles won during the open era, behind Steffi Graf (22 titles) and Chris Evert and Martina Navratilova (18 titles each). She has won more Major titles in singles, doubles, and mixed doubles than any other active player, male or female.

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.

Jennifer Marie Capriati (born March 29, 1976) is a former world number one ranked professional tennis player, and the winner of three women's singles championships in Grand Slam tournaments. Capriati made her professional debut in 1990 at the age of 13 years 11 months when she reached the finals of the hard court tournament in Boca Raton, Florida, losing there to Gabriela Sabatini. Capriati reached the semifinals of the French Open in her debut and later became the youngest ever player to crack the top 10 at age 14 years, 235 days in October of that year. Between 1990 and 1993, Capriati won six singles titles, including a Gold Medal at the 1992 Barcelona Olympics, defeating Steffi Graf in the final. Following a first round loss at the 1993 U.S. Open, the burned out Capriati took a 14-month break from competitive pro tennis. Her personal struggles during this time (including arrests for shoplifting and possession of marijuana) were well-documented by the press.

In 1998, Capriati won her first Grand Slam singles match in five years at Wimbledon. During the next two years, Capriati slowly returned to championship form, winning her first title in six years in Strasbourg, France in 1999 and regaining a top 20 ranking. At the 2001 Australian Open, the reinvigorated Capriati became the lowest seed to ever win the championship when she defeated Martina Hingis (ranked number one in the world at the time) in straight sets for her first Grand Slam championship. She also won the French Open that year, claiming the number one ranking in October. After successfully defending her Australian Open crown in 2002, Capriati became a top ten mainstay until injuries derailed her career in 2004.

Kim Antonie Lode Clijsters (Dutch pronunciation: [kɪm ˈklɛistərs] ( listen); born 8 June 1983) is a Belgian professional tennis player. As of 28 May 2012, Clijsters is ranked no. 47 in singles. Clijsters is a former world no. 1 in both singles and doubles.

Clijsters has won 41 WTA singles titles and 11 WTA doubles titles. She has won four Grand Slam singles titles: three at the US Open, in 2005, 2009, and 2010 and one at the Australian Open in 2011. She has also been runner-up in four Grand Slam singles tournaments, and won the WTA Tour Championships singles title in 2002, 2003, and 2010. In doubles, she won the French Open and Wimbledon titles in 2003. Clijsters announced her retirement with immediate effect on 6 May 2007, but almost two years later, on 26 March 2009, she publicly declared her intent to return to the WTA tour for the 2009 summer hard court season. In only her third tournament back, she won her second US Open title, becoming the first unseeded player and wildcard to win the tournament, and the first mother to win a major since Evonne Goolagong in 1980.