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Thursday September 29th, 2011

The highly anticipated quarterfinal between Maria Sharapova and Petra Kvitova at Tokyo's Pan Pacific Open on Thursday started with a bang and ended with a whimper.

Sharapova was forced to retire in the first set with an ankle injury. Serving at 3-4 in the first set, Sharapova badly twisted her ankle on a split step and fell to the ground. She walked gingerly to her chair and immediately called for the trainer as television close-ups revealed significant swelling in the ankle mere minutes after the injury. After consulting with the WTA trainer, she retired and limped off the court under her own power.

Her retirement put an end to a high-quality match, as both players were well in their rhythm in a rematch of this year's Wimbledon final. Sharapova was to have an MRI, and there was no immediate word about the severity of the injury or whether it will affect her status for next week's China Open in Beijing.

Here's video of Sharapova's ankle roll:

The retirement put Kvitova through to her sixth semifinal of the year. She'll face world No. 2 Vera Zvonareva, who improved to 6-0 against Russian compatriot Maria Kirilenko with a 6-3, 6-3 victory. The two have split their four meetings, with Kvitova winning twice on clay and Zvonareva taking the other two on hardcourts.

In the other half of the draw, Victoria Azarenka and Agnieszka Radwanska advanced to the semifinals. Azarenka found herself in a bit of a tussle with Marion Bartoli in the first set before taking it 7-5, and then ran away with the second set 6-0. Radwanska handled the unseeded Kaia Kanepi, who couldn't consistently find the form that led to her upset of Caroline Wozniacki. Radwanska won 6-2, 7-6 (7). So it will be Kvitova vs. Zvonareva and Azarenka vs. Radwanska on Friday.

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