Midway in her first set against Petra Kvitova, Tokyo 2nd seed Maria Sharapova had to retire when she fell and hurt her left ankle in today's quarterfinals. Sharapova is awaiting the results of an MRI and an examination.
Vera Zvonareva ended countrywoman Maria Kirilenko's impressive run by beating her 6-3, 6-3. Agnieszaka Radwanska defeated Kaia Kanepi, and Victoria Azarenka defeated Marion Bartoli.
In doubles, top seeds Liezel Huber and Lisa Raymond advanced to the semifinals, as did the teams of Victoria Azarenka and Maria Kirilenko, Vania King and Yaroslava Shvedova, and Gisela Dulko and Flavia Pennetta.