Serena Williams withdraws from China Open with knee injury

BEIJING, China -- No. 1 Serena Williams withdrew before her quarterfinal match at the China Open due to a left knee injury, giving Samantha Stosur a walkover into the semifinals. Serena's withdrawal came a day after No. 2 Simona Halep (hip) and sister Venus Williams (viral illness) withdrew from the tournament. Serena will fly back to Europe to see her doctors to assess the extent of the injury, which puts her participation in the year-end WTA Finals in Singapore in question. 

"As a defending champ, you always want to do your best to defend your title," Williams said. "That's why I played yesterday. I've got to at least give it a chance. I've done well here. This is my title. So more than anything, it's extremely frustrating. I wanted to be here. To come all this way and not to take the title, it's just a waste."

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After winning her 18th major title at the U.S. Open in September, Serena's fall campaign has been beset by injury and illness. She retired from her first match at the Wuhan Open last week with a viral illness but looked much sharper this week at the China Open. But Serena began to feel pain in her left knee this week and says she nearly withdrew before her third round match on Thursday night against Lucie Safarova, which she won 6-1, 1-6, 6-2. She skipped her post-match press conference to get treatment on the swelling on her heavily taped knee, but despite the treatment she did not feel fit enough to take the court on Friday.

The extent of the injury is unclear and Serena will get an MRI on her knee when she arrives in Europe. The injury did not affect her movement but she felt it the most when she landed on her left leg after serving. She did not want to speculate about the impact of the injury on her participation at the WTA Finals, which begin on October 17, until she gets a proper diagnosis and treatment plan. 

"If I feel this way for Singapore, I don't think it's smart for me to play," she said. "Other than that I'm just going to see how it goes."