'Devastated': Serena Williams 'shocked' over missing star controversy

Tennis icon Serena Williams is the latest high-profile star to express concern for missing Chinese player Peng Shuai.

Peng has not been heard from since making allegations of sexual assault against a former vice-premier of China in a post on the social media platform Weibo two weeks ago.

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The post was quickly removed and there has been mounting worry for Peng, with Naomi Osaka and Novak Djokovic among those taking to social media to draw attention to the situation.

The head of the WTA expressed his concern about the situation after a letter - purportedly from the Chinese player - appeared on state media to confirm that she was safe and to deny the sexual assault allegations that had been made by her previously.

The governing body of women's tennis has now issued China with a stunning ultimatum over the fate of Shuai.

And Williams is the latest player to publicly express her concern for Peng.

"I am devastated and shocked to hear about the news of my peer, Peng Shuai," 23-time grand slam winner Williams wrote in a Twitter post.

"I hope she is safe and found as soon as possible."

Former World No.1 Kim Clijsters was one to praise the WTA for making a strong stand and demanding answers.

"Strong stand by WTA. All of us players, male and female, need to get behind this. We need to know she is safe!" she wrote.

Tennis world rallies behind Peng Shuai

The tennis community became worried after a message, which was attributed to Peng, was sent to WTA chairman and CEO Steve Simon.

The letter on the China Global Television Network Europe's Twitter page read: "Regarding the recent news released on the official website of the WTA, the content has not been confirmed or verified by myself and it was released without my consent.

"The news in that release, including the allegation of sexual assault, is not true. I'm not missing, nor I am unsafe.

"I've just been resting at home and everything is fine. Thank you again for caring about me."

The WTA chief called for an investigation into Peng's allegations, but has since gone one step further and said China could be stripped of future tennis events - despite the huge sums of money at stake.

Simon says the WTA is prepared to come down hard on China if it is not provided with "verifiable proof" of Peng's safety and whereabouts.

“If at the end of the day we don’t see the appropriate results from this, we would be prepared to take that step and not operate our business in China, if that’s what it came to,” Simon told the New York Times.

“Should we find that what we are asking for cannot happen or will not happen, we are prepared to no longer do business within the region and move forward,” he told TIME during the WTA tour finals in Mexico.

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