Peng's claims against Zhang were the first time China's #MeToo movement has touched the highest echelons of the ruling Communist Party.
Now China has hit back at the WTA, labelling its decision to suspend tournaments in China as "politicising sport", and accusing tennis' governing body of "seriously coercing Peng".
"We are firmly opposed to acts politicising sport," foreign ministry spokesman Wang Wenbin said in a brief comment to reporters when asked about the WTA boycott.
Hu Xijin, editor-in-chief of the Global Times — a branch of Chinese state media — went further.
"WTA is coercing Peng Shuai to support the West's attack on Chinese system," he tweeted.
"They are depriving Peng Shuai's freedom of expression, demanding that her description of her current situation must meet their expectation."
In a strongly-worded editorial, the Global Times criticised the WTA and said it was falsely depicting itself as a "hero team" by committing to suspending tournaments in China regardless of any economic losses.
The statement argued the WTA wouldn't stand to lose much money due to tournaments being cancelled due to Covid-19 anyway.
The editorial also accused the WTA of "radicalism" and acting on behalf of "the West" against China, expressing concerns about potential boycotts of the 2022 Beijing Winter Olympics.
"The WTA has acted as a lever of Western public opinion against China's political system," it said.
"To this end, they repeat the old tricks and once again set the precedent of boycotting sports events for political purposes. This creates new uncertainties for international sports."
It took particular aim at Simon and said the WTA's refusal to accept Peng is safe despite China sharing several photos and videos of her was effectively coercing Peng and depriving her of freedom of expression.
"The WTA has put on an exaggerated show," the Global Times editorial read.
"Their pursuit of "political correctness" is surely top-notch even among Western politicians. To further hype the case, the WTA even disclosed some private information about Peng.
"It is the WTA which claimed Peng's assurance that 'everything is fine' is not credible, and it has been pushing accusations over and over again that she was acting. The WTA's actions are seriously coercing Peng.
"Such coercion has deprived Peng of freedom of expression, forcing her to complain in accordance with the imagination and expectations of Western public opinion, fabricating that she has lost her freedom.
"Peng is an athlete who is destined to be connected with the West. The message the WTA sent to her is that as long as she wants to satisfy the West, she will have to endorse the latter's accusations against China.
"The WTA is expanding its influence in a speculative way. They are bringing politics into women's tennis deeply, and are setting a bad example for the entire sporting world.
"They are opening a Pandora's box. They are betrayers of the Olympic spirit."
IOC claims to have second video call with Peng
China's comments come as the International Olympic Committee (IOC) responded to the WTA's move to suspend its events in China, claiming it has held a second video call with Peng.
"We share the same concern as many other people and organisations about the wellbeing and safety of Peng Shuai" the IOC said in a statement on Thursday.
"This is why, just yesterday, an IOC team held another video call with her. We have offered her wide-ranging support, will stay in regular touch with her, and have already agreed on a personal meeting in January.
"There are different ways to achieve her wellbeing and safety. We have taken a very human and person-centred approach to her situation."
Last month, IOC president Thomas Bach had a video call with Peng in which she said she was safe, according to the IOC.
However, the IOC was slammed for failing to address her allegations of sexual assault and IOC member Dick Pound's defence of the video call was roundly criticised.
The IOC stressed it remains worried about Peng's wellbeing and vowed to address their concerns via "quiet diplomacy" with China.
"Since she is a three-time Olympian, the IOC is addressing these concerns directly with Chinese sports organisations. We are using "quiet diplomacy" which, given the circumstances and based on the experience of governments and other organisations, is indicated to be the most promising way to proceed effectively in such humanitarian matters.
"The IOC's efforts led to a half-hour videoconference with Peng Shuai on 21 November, during which she explained her situation and appeared to be safe and well, given the difficult situation she is in.
"This was reconfirmed in yesterday's call. Our human and person-centred approach means that we continue to be concerned about her personal situation and will continue to support her."
