MELBOURNE, Australia — Xiao, a Chinese-born and Melbourne-based artist, was disturbed that the plight of the Chinese tennis star Peng Shuai had slipped off the radar ahead of the first Grand Slam tournament of the year. So she designed a T-shirt, and much to the dismay of Australian Open organizers, wore it to Melbourne Park.

Xiao was concerned that the unvaccinated tennis star Novak Djokovic’s fight with the Australian government had overshadowed the plight of Peng, one of China’s most popular tennis stars, who has mostly disappeared from public view since she accused a former top Chinese leader of sexual assault. Xiao’s shirt had on the front a picture of Peng’s face and on the back the slogan “Where is Peng Shuai?”, a message that has been used heavily online as a call to confront the Chinese Communist Party about the #MeToo accusation that prompted the women’s tennis tour to suspend its tournaments in China.

Security guards later told Xiao, who also brought a sign with the slogan, that the items were not permitted, citing a tournament policy banning fans from making political statements.

“It’s a reminder for people to not forget about Peng Shuai, especially since we had a huge Djokovic drama recently,” said Xiao, 26, who spoke on the condition that her full name not be used because of concerns for her safety after calling out the Chinese government.

On Tuesday, after criticism from the 18-time major singles champion Martina Navratilova and others, the Australian Open softened its policy and is now allowing T-shirts and other personal messages supporting Peng, who has remained top of mind for many people involved in women’s tennis since her accusation first surfaced in November.

Peng, a U.S. Open singles semifinalist and former world No. 1 in doubles, said then — in a post on her verified account on the social media site Weibo — that she had been sexually assaulted by Zhang Gaoli, a former vice premier of China. In the post, Peng wrote that they had once been involved in a consensual relationship.

The post was taken down minutes later. Online discussion of the allegation was censored within China, and Peng disappeared from public view for weeks while tennis officials and fellow players tried unsuccessfully to reach her. Peng, a three-time Olympian, later had conversations via video with International Olympic Committee President Thomas Bach and other Olympic officials.

In a statement after the first of those meetings in November, the I.O.C. announced that Peng had said she was “safe and well,” and she has since been seen publicly in China in several social media posts. On Dec. 1, Steve Simon, chief executive of the Women’s Tennis Association, suspended tournaments in the country and renewed his call for a “full and transparent” investigation from the Chinese authorities.

Peng later told a reporter for a Singaporean newspaper in Beijing that her initial post had been misunderstood and that she had “never said or written that anyone has sexually assaulted me.”

But the WTA, whose leaders still have been unable to make direct contact with Peng, has not softened its stance or its demands, fearing that she has been coerced into the retraction.

“We appreciate seeing the support continue for Peng Shuai,” Simon said Wednesday in an email. “The WTA is proud of Peng Shuai in speaking out for what is right, and we continue with our unwavering call for confirmation of Peng’s safety along with a full, fair and transparent investigation, without censorship, into her allegation of sexual assault. This is an issue that can never fade away.”

Magda Linette, a leading Polish player and member of the WTA player council, said she hoped Peng could speak with players directly or with Simon. “If we could see her in an environment where we know she is not being really controlled and we can have at least a conversation, because she has been refusing that, I think that would be a really good step to trying to rebuild the trust, trying to rebuild the relationship again to see how things are going and how she is actually,” Linette said.

Alizé Cornet of France, a quarterfinalist at the Australian Open and one of the players to raise concerns about Peng’s safety in November, said some of her fears had been allayed.

“It’s not the huge concern I had in November where I imagined she might have been buried in a ditch,” Cornet said last week.

Cornet added that she believed that Peng was not in physical danger, but that “I’m concerned to know how things will go for her and what will become of her.”

The renewed attention on Peng comes at a politically sensitive time with the Winter Olympics scheduled to begin in Beijing on Feb. 4.

“It is kind of sad to see her story, especially when we are technically in an Asia-Pacific Slam, kind of not be a topic anymore,” said Jessica Pegula, an American player who reached the quarterfinals in Melbourne. “It’s disappointing, but it is kind of how the media is. Stuff blows up. Then it goes away, and it blows up again, and something else comes.”

Pegula, who said she was not reassured by Peng’s recent video appearances, added: “Maybe it will catch up more when the Olympics come around.”

The Australian Open, one of the four Grand Slam tennis tournaments, has long positioned itself as the “Grand Slam of Asia-Pacific” in part because of concerns that China or another nation in the region might attempt to usurp its status. A state-owned Chinese liquor company, Luzhou Laojiao, has been a major tournament sponsor since 2019 and holds the naming rights for one of the principal show courts. Tennis Australia, which runs the event, has an office and presence in China and has backed tournaments in China that awarded wild-card entries into the Australian Open.

The Australian Open also has an agreement with CCTV, the national Chinese broadcaster, which has been broadcasting men’s and women’s matches from this Australian Open.

But Chinese television did not broadcast the women’s tournaments in 2022 that were played ahead of the Open despite owning the rights. It is unclear whether this constitutes a boycott. In 2019, CCTV stopped airing N.B.A. games after Daryl Morey, the general manager of the Houston Rockets at the time, expressed support for pro-democracy protesters in Hong Kong.

No events for the WTA or ATP, the professional men’s tennis tour, have been held in China since early 2020 because of the coronavirus pandemic, which had shut down international sports events in the country before the upcoming Olympics. The WTA had made China one of the pillars of its tour and agreed to a lucrative 10-year deal to stage its year-end championships, the WTA Finals, in Shenzhen. But the event, first held there in 2019, was moved to Guadalajara, Mexico, last year because of the pandemic with just eight weeks to prepare.

The WTA would need to lift the suspension on Chinese tournaments if they were to take place this year. The China swing is scheduled for September, October and November. The WTA has not given a deadline but wants to finalize its fall schedule much earlier than it did in 2021. With China unlikely to launch a formal investigation into Peng’s allegations of sexual assault, cancellation of this year’s China swing appears likely, although Simon has said that this would not necessarily end the tour’s commitment to Chinese tournaments in 2023 and beyond.

The ATP has made statements of support for Peng but has not suspended any events as a result of her situation. Pegula said she was disappointed the ATP had not done more. “I just think it was the right thing to do,” she said. “I wish they would have, and I guess they still could. We’ll see.”

Reilly Opelka, one of the leading American male players, called the ATP’s hands-off approach “lame” and “weak.”

“We rely so much less on China than the WTA does and look at that statement,” he said. “And that digs into a deeper problem: Why didn’t enough ATP players speak out? Is it conflicts of interest? It’s hard to say.”

Interest in tennis in China boomed after Li Na became the country’s first Grand Slam singles champion, winning the 2011 French Open and 2014 Australian Open. Though no Chinese player has matched those results, promising talents are on the rise, including Wang Xinyu, a tall and powerful 20-year-old who pushed the No. 2-seeded Aryna Sabalenka to three sets in the second round of the Australian Open last week.

Chinese players in Melbourne have refused one-on-one interviews with The New York Times, but Xu Yifan, a women’s doubles specialist, said during a news conference that it was important for tennis’ future in China to have tour events in the country. “Especially for Chinese players, we all enjoy,” said Xu, who declined to comment on Peng Shuai’s situation.

“We didn’t really focus on it,” she said. “We just tried to focus on our tennis most of the time.”

The WTA may be able to cover much of its lost Chinese revenue by adding events elsewhere. But there is still concern about the future.

“We had a bunch of amazing tournaments in China, and I think in response, they’ve had so many players coming up and really have now so many juniors that are really good and tennis has been the strongest ever really in China,” Linette said. “So, I think for both of us, for the sake of the WTA and for China if it wants that their players keep developing and still have a chance to go out and do something more in tennis, it’s better for both that this situation be resolved in a peaceful manner.”

For now, it remains a delicate dance. The artist Xiao said she hesitated before bringing her message of support for Peng to the Australian Open. “But I just feel like I had to do what I had to do,” she said.

Xiao described the atmosphere on her first day at the tournament, Wednesday, as “quite chill.” “Two guards came and they just asked me, ‘Oh, what is Peng Shuai?’” Xiao recalled. “We explained to them the situation and they just said, ‘Oh, that’s an unfortunate story,’ and they just left. They were really nice about it, actually.”

After posting pictures of her protest at the tournament on social media, Xiao was contacted by local activists who wanted to join her. On Friday, they went to a third-round women’s singles match featuring the Chinese player Wang Qiang, hoping they would be seen on broadcasts of the match back in China.

While the group was moving between Wang’s match and a Naomi Osaka practice session, the situation turned more confrontational, leaving Xiao “on the verge of a panic attack” as an encounter between the activists and security guards was filmed for use on the activists’ social media accounts.

Xiao said she was offered a chance to stay at the tournament if she stashed the offending items in a booth outside the entrance but chose to leave Melbourne Park instead. Hours later, on Friday evening, Xiao returned and wrote “Where is Peng Shuai?” in chalk on an exterior wall of the tournament grounds.

Xiao said she “knew the rules from the beginning” against political banners at the tournament and was not surprised that Tennis Australia initially enforced them.

“I kind of expect it,” Xiao said, “because they have Chinese sponsors, right?”

Craig Tiley, chief executive of Tennis Australia, said in an interview on Monday that the tournament’s view was not influenced by its Chinese commercial interests. He said Tennis Australia backed the WTA’s stance on Peng Shuai and had attempted to use its connections in China to establish contact with her.

“It doesn’t have to just be on a political or commercial issue,” Tiley said. “If we make the assessment that they come in to disrupt the comfort and safety of our fans, it’s not going to be welcome. But if they want to come in with a T-shirt and it says, ‘Where is Peng Shuai?’ they can do that. We don’t have a problem with that.”

The shift by tournament officials does not change the question posed by Xiao and others. The activists who joined the artist have raised money to pay for a thousand more T-shirts that they plan to hand out to spectators before the women’s singles final.