Ann Li of the United States celebrates after winning the women's singles first round match between Zhang Shuai of China and Ann Li of the United States at Australian Open in Melbourne Park, Melbourne, Australia on Feb. 9, 2021. (Xinhua/Bai Xuefei)

Ann Li of the United States returns a shot during the women's singles first round match between Zhang Shuai of China and Ann Li of the United States at Australian Open in Melbourne Park, Melbourne, Australia on Feb. 9, 2021. (Xinhua/Bai Xuefei)

Zhang Shuai of China reacts during the women's singles first round match between Zhang Shuai of China and Ann Li of the United States at Australian Open in Melbourne Park, Melbourne, Australia on Feb. 9, 2021. (Xinhua/Bai Xuefei)

Zhang Shuai of China serves during the women's singles first round match between Zhang Shuai of China and Ann Li of the United States at Australian Open in Melbourne Park, Melbourne, Australia on Feb. 9, 2021. (Xinhua/Bai Xuefei)

Zhang Shuai of China returns a shot during the women's singles first round match between Zhang Shuai of China and Ann Li of the United States at Australian Open in Melbourne Park, Melbourne, Australia on Feb. 9, 2021. (Xinhua/Bai Xuefei)

Zhang Shuai (R) of China greets with Ann Li of the United States after the women's singles first round match between Zhang Shuai of China and Ann Li of the United States at Australian Open in Melbourne Park, Melbourne, Australia on Feb. 9, 2021. (Xinhua/Bai Xuefei)

Zhang Shuai of China returns a shot during the women's singles first round match between Zhang Shuai of China and Ann Li of the United States at Australian Open in Melbourne Park, Melbourne, Australia on Feb. 9, 2021. (Xinhua/Bai Xuefei)

Zhang Shuai of China returns a shot during the women's singles first round match between Zhang Shuai of China and Ann Li of the United States at Australian Open in Melbourne Park, Melbourne, Australia on Feb. 9, 2021. (Xinhua/Bai Xuefei)