JINAN, Shandong province: China's top-ranked player, Li Na, was forced to quit at the National Games due to knee injury in her first singles match yesterday.

After losing the first set 0-6 to Chen Yanchong of Guangdong, Li, the nation's No 1 and also the world No 16, called off the match and walked out of the court accompanied by her husband Jiang Shan. The 27-year-old Li, who has been battling a right knee ligament sprain, withdrew from the team event held in July because of the same problem.

"It was difficult for Li to walk after the first set and apparently she could not continue her match," the head umpire, Wang Li, said.