Former world No.1 Venus Williams suffered a shock defeat by Chinese player Wang Qiang in the French Open first round on Sunday.

The 37-year-old ninth seed was well short of her best as Wang claimed a 6-4, 7-5 victory and gained a measure of revenge for her first-round loss to Venus at Roland Garros last year.

The seven-time Grand Slam champion has now lost both her matches at major tournaments this year, having reached the Australian Open and Wimbledon finals in 2017.

Wang, the world No.91, has never made the third round of a Slam, and will face Petra Martic of Croatia for a place in the last 32 after the biggest win of her career.

World No.9 Venus will now turn her attention to playing the doubles tournament with her sister Serena, who is competing in a Grand Slam event for the first time since last year's Australian Open after giving birth to her daughter.