The WTA Tour on Sunday (Nov 14) called on the Chinese government to investigate allegations of sexual assault made by Peng Shuai against a former Chinese vice premier, while also demanding an end to censorship of the former top-ranked doubles player.
Peng, one of China's biggest sporting stars, alleged on her Weibo social media account on Nov 2 that Zhang Gaoli, who became a member of the Politburo Standing Committee - China's top decision-making body - coerced her into sex and they later had an on-off consensual relationship.
Peng said in the post, which was deleted around half an hour after it was published, that she could provide no evidence to back her allegations.
The China Tennis Association did not respond to a Reuters request for comment.
China's Internet is heavily censored and the private lives of top leaders are an especially sensitive subject.
Concerns among the global tennis community have grown as Peng has not been seen since the post.
The WTA said in a statement that it will seek a "full, fair and transparent investigation into sexual assault allegations" against a former Chinese leader.
"The recent events in China concerning a WTA player, Peng Shuai, are of deep concern," said WTA Tour chairman and CEO Steve Simon in a statement.
"Peng Shuai, and all women, deserve to be heard, not censored.
"Her accusation about the conduct of a former Chinese leader involving a sexual assault must be treated with the utmost seriousness."
Peng was the world number one doubles player in 2014, the first Chinese player to achieve a top ranking, after winning the doubles titles at Wimbledon in 2013 and the French Open in 2014.
China, the focus of the Tour's most aggressive expansion over the last decade, hosted nine tournaments in the 2019 season, including the elite WTA Finals, with a total US$30.4 million prize money on offer.
The season-ending WTA Finals, contested by the world's top eight singles players and eight doubles teams, had a prize purse of US$14 million in 2019 when it was played in Shenzhen for the first time.
The Finals was cancelled last year due to the COVID-19 pandemic and moved this year to Guadalajara, Mexico.
The WTA said that the tournament will return to Shenzhen from 2022 and the Chinese city will host every edition until 2030.
"I think everybody fully understands what's at stake here on many different fronts as we're going through it," Simon told the New York Times on Sunday.
"I think we're certainly, from players to board to council, fully united that the only acceptable approach is that of doing what is right."
Simon told the Times no one at the WTA Tour has talked directly to Peng but has received assurances from the Chinese Tennis Association that she is safe.
"We've received confirmation from several sources, including the Chinese Tennis Association, that she is safe and not under any physical threat," Simon told the Times.