Wang Qiang of China upset the odds in the first round of the French Open on Sunday by knocking out five-time Wimbledon champion Venus Williams 6-4, 7-5.

The unseeded Chinese rewrote history and avenged her loss to No.9 seed Williams on the opening day at Roland Garros last year. She was also beaten by the American veteran at Wimbledon a few weeks later.

In what was just her second career victory over a top-10 player, Wang, 85th in this week's newly refreshed WTA rankings, attempted to play down her victory in her post-match comments, saying only that the win had been “one of” the best of her career.

Wang, who made it into the main draw at Roland Garros for the fourth time, finished her first break after both players had several deuces in the 12-minute first game. Plagued by unforced errors, Williams made a timely comeback in the second set, going up 3-0 largely on the strength of her fierce backhand. But the resilient Wang found a way to build on the two previous matches and played more assertively to collect three games in a row.

The 26-year-old refused to surrender and after the two players shared the next four games for a 5-5 tie, Wang broke Williams' service for the fourth time in the 11th game of the second set and recorded a stunning victory.

The seven-time Grand Slam singles winner suffered a disastrous 35 unforced errors despite notching 28 winners, also inferior to Wang in terms of points on first and second serves.

The defeat marked the first time the American runner-up in 2002 lost her opening match at Roland Garros since 2001, and the only time in her career she has lost consecutive Grand Slam opening round matches following her exit at the Australian Open in January.

After the match, Williams was full of praise for her frequent Grand Slam opponent. "I think [Wang] just played well," said the former World No.1. "I mean, all the times we've played, she's played great. I think her game just got better and better during the match."

Although the first win, it is not Wang’s first impressive game against Williams. She drew the American twice last season and played valiantly both times, taking the tennis star to a tiebreaker in the first round in Paris and extending her to three sets in the second round at Wimbledon.

Of the other Chinese players in action on Sunday, Zheng Saisai lost her singles opener match at the 2018 French Open to doubles specialist Ekaterina Makarova of Russia 6-4, 6-1. Zheng's compatriot Wang Yafan also bowed out from the clay Grand Slam with a 6-2, 6-3 loss to Croatian Petra Martic.

Wang, who has never made the third round of a slam, will next face World No.35 Martic for a place in the last 32 after the biggest win of her career.