China's Li Na, Peng Shuai knocked out of French Open

Sixth seed and former champion Li Na of China became the biggest name to fall at the French Open as she was knocked out by Bethanie Mattek-Sands in the second round here on Thursday.

Li's two compatriots Zheng Jie and Peng Shuai had mixed fortunes, with Zheng beating Melanie Oudin and Peng losing to 2011 Wimbledon champion Petra Kvitova.

Li, China's first Grand Slam singles champion, lost to the 67th-ranked American 7-5, 3-6, 2-6, in a match interrupted by rain three times at court No. 1.

The 31-year-old Li, the titlist at Roland Garros in 2011, took an early lead of 4-0 in the first set but Mattek-Sands won the next five games to make it 5-4. Li managed to grab the next two games for the first set but she looked far from a winner in the next two sets.

It was Li's worst results at the French Open since she made her debut in 2006.

Li said that her defeat had nothing to do with the rain delay although she admitted that this year's weather condition in Paris was tough.

"Yeah, this is very tough condition," she said. "But for both players the conditions are the same. I should find out what happened."

For Mattek, it was one of the greatest victories in her career.

"At a Grand Slam it's my biggest win. I'm really proud of myself that I was able to close out the match the way I did," said the 28-year-old, who repeated her best result at the French Open she achieved in 2011.

Zheng, a former Wimbledon semifinalist, defeated Oudin 6-3, 6-1 and Peng lost to Kvitova 6-4, 6-3.