The Women’s Tennis Association (WTA) has said that appearances in the media by Peng Shuai on Sunday "do not alleviate" its "significant concerns about her well-being".
At the weekend, the 35-year-old gave a short interview which was uploaded by Singapore outlet Lianhe Zaobao.
READ MORE: Chinese tennis star denies sex assault allegations in new video
In it, Peng said: "I need to stress one point that is extremely important, I have never said or written that anyone has sexually assaulted me, I have to clearly stress this point."
Earlier in November, however, the former Wimbledon and French Open doubles champion appeared to have done just that against former Chinese vice premier Zhang Gaoli in a post on local social media site Weibo which was later taken down.
Peng said the Weibo outburst was a "private matter" that "people have many misunderstandings" about, and added that she had been living in Beijing without supervision while not mentioning Zhang.
In a statement, however, the WTA, which has canceled its tournaments in China in response to the incident, said it remains "steadfast in our call for a full, fair and transparent investigation, without censorship, into her allegation of sexual assault, which is the issue that gave rise to our initial concern."
"It was again good to see Peng Shuai in a public setting and we certainly hope she is doing well," the WTA went on.
"As we have consistently stated, these appearances do not alleviate or address the WTA’s significant concerns about her well-being and ability to communicate without censorship or coercion."
Peng soon disappeared from the public eye following her Weibo post, but held two video calls with the International Olympic Committee (IOC) and its chief Thomas Bach, for which the organization was criticized and accused of being in bed with the Chinese state.
There had been previous sightings of her at a Beijing tennis tournament and in a video enjoying dinner at a restaurant which was uploaded to Twitter by a Chinese state media editor.
But Sunday marked her most active day since the controversy broke out. Before the Lianhe Zaobao interview was made public, a journalist from state-owned newspaper Global Times had also shared clips and photos of Peng at a Shanghai event.
In a video that Qingqing Chen claimed was sent to her by a friend, Peng is captured laughing with basketball icon Yao Ming.
Later, Chen then shared a photo of Peng in front of the iconic Yangpu bridge with Ming, former table tennis player Wang Liqin and Olympic sailing gold medalist Xu Lijia, with all this footage including the interview where she denied her claims believing to have come from the Shangai stop of a cross-country skiing tour.
As of yet, Beijing hasn't commented on Peng's interview or the WTA's statement with the Winter Olympics fast approaching in February.
Previously, though, when the WTA announced the suspension of competitions in China, the state said it "opposes the politicization of sports".
In her video, Peng also claimed that a letter she wrote to the WTA's chief Steve Simon denying the allegation of assault had been correctly translated by Chinese state media.
When he received it, Simon said he "had a hard time believing" Peng had written the email herself.