At a time of far too much equivocation — by corporations, governments and nonprofits — about the rampant violation of human rights in China, a statement from Steve Simon, chairman and chief executive of the Women’s Tennis Association (WTA), rings out like the proverbial fire bell in the night. At issue is the suspicious disappearance of Chinese professional tennis player Peng Shuai, a 35-year-old woman formerly ranked No. 1 in doubles worldwide. Ms. Peng vanished after Nov. 2, when she posted an accusation of being sexually assaulted by a former member of the Chinese Communist Party Politburo, Zhang Gaoli. Her only purported communication since speaking out against one of China’s most powerful men was a statement released in her name by state media, claiming that she is “resting at home” and retracting her charges against Mr. Zhang.

Mr. Simon replied, forthrightly, that this possibly coerced or fabricated comment only increased his concern; he demanded to be put in touch directly with Ms. Peng. The issues of sexual assault and censorship are so serious, he added in an interview with CNN on Friday, that the WTA is “definitely willing to pull our business [from China] and deal with all the complications that come with it. Because this is certainly, this is bigger than the business.”

In that one sentence, Mr. Simon — on behalf of the women professionals who play on the tour — expressed more moral courage regarding China than pro sports counterparts such as the National Basketball Association have managed to muster in, well, ever. Certainly corporations such as Coca-Cola that are sponsoring the Winter Olympics in Beijing could learn from the WTA’s example.

There seems to be no point in hoping that the International Olympic Committee itself will rise to the occasion. In a statement shamefully evocative of the IOC’s darkest episode — the Olympic movement’s accommodation of Nazi Germany in the 1930s — the IOC on Thursday declared itself “encouraged by assurances that she is safe.” The IOC later said in an emailed statement: “Experience shows that quiet diplomacy offers the best opportunity to find a solution for questions of such nature. This explains why the IOC will not comment any further at this stage.”

What experience really shows is that dictatorships seek to co-opt ostensibly neutral global institutions such as the IOC and exploit their silence or indulgence. Feb. 4, the opening day of the Beijing Games, is fast approaching, which means that time is rapidly running out for the world to decide whether, and how, to prevent the Olympiad from turning into an uncontested showcase for Xi Jinping’s dictatorship. President Biden said Thursday he is considering a “diplomatic boycott,” whereby no U.S. officials would attend, a step that would be most effective if taken in concert with other democracies. Meanwhile, we must hope that the WTA’s firm stand on China’s treatment of Peng Shuai will help her regain the freedom she has seemingly lost. We already know that it has set a standard for all who would exercise leadership.