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The Olympic tennis event was dealt a further blow on Sunday with the news that women's top seed Ana Ivanovic had to pull out of the tournament with an injury to her right thumb.
The French Open champion sustained the injury when she returned to training after losing at Wimbledon and had not been able to practise since arriving in China.
She had been due to face Ukraine's Mariya Koryttseva in the first round on Monday, but after consulting with a doctor on the inflammation, she said she needs more rest.
"This is one of the worst moments of my career," said the devastated Serbian, who will also be deposed as world number one by compatriot Jelena Jankovic on Monday.
Ivanovic added the injury may take two weeks to heal and she still hopes to play in the US Open, which begins on 25th August.
She is the latest big name to withdraw after Maria Sharapova, Tatiana Golovin and Amelie Mauresmo had already pulled out of the competition, while 1996 champion Lindsay Davenport has decided not to play in the singles.
Second seed Jankovic, who is due to play Zimbabwe's Cara Black in the first round, is still a doubtful starter after picking up a calf strain.
Ivanovic's withdrawal came on a rain-hit day at the tennis tournament where only nine of a scheduled 45 matches were completed.