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Safin was born in Moscow to Tatar parents, Mubin ("Mikhail") Safin and Rauza Islanova. He speaks Russian, English, and Spanish as well as his native Tatar. His parents are former tennis players and coaches. His younger sister, Dinara, is a former world number one professional tennis player and silver medalist at the 2008 Olympic Games in Beijing.

Safin held the No. 1 ATP ranking for 9 weeks during 2000 (making him the tallest No. 1 ranked player of all time) when he won his first Grand Slam tournament at the US Open, becoming the only Russian in history to win this tournament in the men's singles draw, by defeating Pete Sampras in straight sets. He barely missed finishing the year as #1, the top spot being overtaken by Gustavo Kuerten at the last match of the season, the final of the 2000 Tennis Masters Cup and ATP Tour World Championships (3-0 win over Andre Agassi).  Safin reached three more Grand Slam finals, all at the Australian Open (2002, 2004, and 2005). He has cited nervousness as the reason for his loss in the 2002 event, and physical exhaustion for the 2004 loss. He defeated Lleyton Hewitt in the 2005 final to secure his second Grand Slam in five years. En route to this final, he defeated top-ranked Roger Federer in a five-set semifinal match. Safin described the match as "a brain fight." He also defeated future world No. 1 Novak Djokovic, who was making his first appearance in the main draw of a Grand Slam tournament, in the first round losing just three games.  His best result at Wimbledon was reaching the semifinals in 2008, beating world No. 3 Novak Djokovic en route. He often lost in the first or second rounds in other years, although he made the quarterfinals in 2001, losing in four sets to eventual champion Goran Ivanisevic. Safin dismissed his performance in the 2001 tournament as a result of luck. Safin disliked playing on grass. Safin has said: "It's difficult to [break serve]. It's difficult to play off the baseline because [of] a lot of bad bounces." With Safin's semifinal performance at Wimbledon in 2008, he became the fourth of five active players at the time to reach the semifinals in all four Grand Slams, joining Roger Federer, David Nalbandian, and Novak Djokovic. Other active players have since then joined the list.
Marat Safin