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
2015 US Open – Women's Singles 2015 US Open – Women's Singles Serena Williams was the three-time defending champion, but she was defeated in the semifinals by the unseeded Roberta Vinci. In doing so, Williams missed the opportunity to become only the fourth woman (after Maureen Connolly, Margaret Court and Steffi Graf) to complete a calendar year Grand Slam by winning the tournament. She was also trying to set a new Open Era record by winning her seventh US Open singles title. Flavia Pennetta won her first Grand Slam championship, defeating Vinci in the final, 7–6, 6–2. Pennetta was the first maiden Grand Slam champion since