FILE - Peng Shuai, of China, returns a shot to Maria Sakkari, of Greece, during the second round of the US Open tennis championships on ug. 29, 2019, in New York. China's Foreign Ministry is sticking to its line that it isn't aware of the controversy surrounding tennis professional Peng Shuai, who disappeared after accusing a former top official of sexually assaulting her. A ministry spokesperson said Friday that the matter was not a diplomatic question and that he was not aware of the situation. (AP Photo/Michael Owens, File)

FILE - Peng Shuai, of China, serves to Maria Sakkari, of Greece, during the second round of the US Open tennis championships Thursday, Aug. 29, 2019, in New York. (AP Photo/Eduardo Munoz Alvarez, File)