Samantha "Sam" Jane Stosur is an Australian professional tennis player, best known for winning the 2011 US Open singles title. Stosur's professional debut into the tennis world was in 1999 on the ITF circuit. In 2001 she won four straight ITF titles. In 2006, Stosur and Raymond won 18 straight matches, winning titles in Tokyo, Memphis, Indian Wells, and Miami. They also won in Charleston, at the French Open, and the WTA Tour Championships. The following year, Stosur and Lisa Raymond successfully defended their doubles titles in Tokyo, Indian Wells, and Miami and proceeded to win the German Open in Berlin. In 2010, Stosur began her clay season at the Family Circle Cup, where she defeated Vera Zvonareva for her fifth consecutive victory over the Russian and won her second and biggest WTA title, which put her back inside the top 10 at world no. 10. She is the only Australian woman to have won this title. Stosur was the only player in 2010 to defeat both current world no. 1 players, Serena Williams and Caroline Wozniacki. 2011 was the year Stosur won her very first Grand Slam tournament singles title and that too by crushing the three-time champion Serena Williams at her first US Open singles final. She competed in the 2012 London Olympics but lost in the first round to Carla Suárez Navarro. She is a former world No. 1 on the WTA Tour in doubles.