Victoria Azarenka out with injury

LONDON -- Second-seeded Victoria Azarenka has pulled out of Wimbledon after hurting her right knee in her opening-round win.

Early in the second set of her match against Maria Joao Koehler, Azarenka did the splits near the baseline then crumpled to the grass, clutching her right knee and sobbing.

Azarenka recovered after a medical timeout to finish out the 6-1, 6-2 victory Monday, but she moved gingerly after falling and said she wasn't sure about the extent of the injury.

On Wednesday, minutes before her second-round match against Flavia Pennetta, Azarenka pulled out of the tournament.

Azarenka said medical tests showed she had a bone bruise rather than a tear but that she was unable to recover in time.

"We tried to do everything as possible, but it was just very significant fall," she said. "To recover in two days after that seems impossible with the compensation on the entire body by finishing that match."

Considered one of Serena Williams' toughest matchups, Azarenka has won the past two Australian Opens and had reached the semifinals in her last two Wimbledon appearances.

Seven players were knocked out of Wimbledon on Wednesday by withdrawals or mid-match retirements, believed to be the most in one day at a Grand Slam tournament in the 45-year Open era.

The International Tennis Federation said it believed the previous high total for one day at a major tournament was five, which happened on the first day of competition at Wimbledon last year, June 25.

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