2009 US Open – Women's Singles 2009 US Open – Women's Singles Serena Williams was the defending champion, but was defeated in the semifinals by the eventual champion Kim Clijsters. Clijsters defeated first time Grand Slam finalist Caroline Wozniacki in the final to win her second US Open title. Clijsters became the first unseeded player and wild card to win the tournament, and the first mother to win a major since Evonne Goolagong in 1980. Following her win, she made 19th in the rankings. This was the final Grand Slam appearance for former two-time Grand Slam champion, Amélie Mauresmo, who lost to Aleksandra Wozniak in the
2010 US Open – Men's Singles 2010 US Open – Men's Singles Juan Martín del Potro was the defending champion, but chose not to participate this year, after undergoing a wrist operation in May and only starting to practice again in August. Del Potro was the third man in the Open Era not to defend his US Open title, after Ken Rosewall in 1971 (due to conflicts between the World Championship Tennis (WCT) and the International Lawn Tennis Federation (ILTF)), and Pete Sampras in 2003 (who unofficially retired after the 2002 final). For the first time in U.S. Open history, no American player was seeded in