against Marion Bartoli, and went on to upset Elena Dementieva in the quarterfinals before losing to Caroline Wozniacki in the semifinals. Radwańska entered the 2010 Sony Ericsson Open, where she was defeated in the quarterfinals by Venus Williams. At Wimbledon, she was defeated in the fourth round by Li Na, whom she had beaten at the same stage the previous year. Radwańska reached the final of the Southern California Open in San Diego, falling to Svetlana Kuznetsova. Due to a stress fracture in her foot, Radwańska's 2010 season ended at the China Open, where she lost a three-set match to Angelique Kerber. 2011: Asian double in Tokyo and Beijing Radwańska reached the quarterfinals of the Australian Open, losing to eventual champion Kim Clijsters. She went on to reach the fourth round in Indian Wells, where she lost to Victoria Azarenka, and the quarterfinals in Miami, losing to Vera Zvonareva. However, she won the Miami doubles title with Daniela Hantuchová, defeating Nadia Petrova and Liezel Huber. She went on to reach the fourth round of the French Open, losing to Maria Sharapova. Radwańska suffered her earliest ever exit at Wimbledon, when she was defeated in the second round by Czech qualifier Petra Cetkovská. At the San Jose Open, Radwańska advanced to the final and defeated rival Vera Zvonareva, in straight sets. With the victory, she earned her first title since winning in Eastbourne in 2008. At the Rogers Cup in Toronto, she once again defeated Zvonareva in the third round, coming back from a 0–4 deficit in the second set. She went on to lose a three-set semifinal match against Samantha Stosur. After defeating her sister Urszula in the first round of the US Open, she was upset in the second round by eventual semifinalist Angelique Kerber. She avenged this loss at the Toray Pan Pacific Open, defeating Kerber in three sets before advancing to the final, where she won her third straight match against Vera Zvonareva, earning her first Premier 5 title. At the China Open, she defeated Zheng Jie, Sofia Arvidsson, Ana Ivanovic (who retired from their quarterfinal match due to a back injury), and Flavia Pennetta in straight sets, before winning a three-set final against Andrea Petkovic. She qualified for her first season-ending championship in Istanbul, taking the 8th spot when Marion Bartoli was unable to win the title in Moscow. Going into the Tour Championships, Radwańska was