Samantha "Sam" Jane Stosur (born 30 March 1984) is an Australian professional tennis player. Stosur is currently ranked World No. 18 by the WTA. She is a former World No. 1 in doubles, a ranking which she held for 61 weeks. Stosur is also a former World No. 4 in singles.
Stosur won the 2011 U.S. Open, defeating Serena Williams in the final and becoming the first Australian woman since Evonne Goolagong Cawley in 1980 to win a Grand Slam singles tournament and just the second Australian woman in history to win the US Open after Margaret Court. Stosur has won five other Grand Slam titles to date; two in women's doubles; and three in mixed doubles. She was also a finalist at the singles event at the 2010 French Open, where she lost to Francesca Schiavone.
Stosur won the 2011 U.S. Open, defeating Serena Williams in the final and becoming the first Australian woman since Evonne Goolagong Cawley in 1980 to win a Grand Slam singles tournament and just the second Australian woman in history to win the US Open after Margaret Court. Stosur has won five other Grand Slam titles to date; two in women's doubles; and three in mixed doubles. She was also a finalist at the singles event at the 2010 French Open, where she lost to Francesca Schiavone.