Serena Williams of the U.S. shakes hands at the net with Caroline Wozniacki of Denmark after winning their semi-final match at the U.S. Open tennis tournament in New York
Serena Williams of the U.S. shakes hands at the net with Caroline Wozniacki of Denmark (L) after winning their semi-final match at the U.S. Open tennis tournament in New York, September 10, 2011. Reuters

Serena Williams and Maria Sharapova have withdrawn from the China Open that starts on Saturday.

World number two Sharapova, 24, twisted her ankle against Wimbledon champion Petra Kvitova in the Pan-Pacific Open quarter-finals on Thursday and was forced to quit the Tokyo tournament.

The good news is the MRI scan showed no big damage to my ankle. I will do my best to recover in time for Istanbul, the Russian said on her website.

Former world number one Williams has pulled out of the Beijing event for the second year in a row, according to the China Open website.

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