China's Zheng Qinwen rates her first round show just 70 out of 100

MELBOURNE, Jan. 12 (Xinhua) -- Olympic champion Zheng Qinwen of China secured a victory in her opening match at the Australian Open but rated her performance only "70 points" out of 100.

"If I had taken it at 5-3, I might have given myself 90 points," Zheng told reporters after the match.

Zheng, the fifth seed and last year's beaten finalist, endured unexpected challenges during her one-hour, 59-minute fi