Liu Xiang, China's best hope of athletics gold at the Beijing Olympics, needs time to recover from a tight hamstring and might not be fit to run in his final warm-up meet in the US this weekend, his coach said.

The 110-meter hurdles world champion and world record holder's preparations for his Olympic title defence have been seriously disrupted by the injury, which caused him to withdraw from the Reebok Grand Prix in New York last weekend.

The 24-year-old, currently receiving treatment in southern California, had planned to run in only two meetings in the US before returning to Beijing to acclimatize before the August 8-24 Games.

Coach Sun Haiping, however, said it was by no means certain that Liu would take part in the Prefontaine Classic in Eugene, Oregon on Sunday.

"Please be patient and give him some time to recover," he told Oriental Sports Daily yesterday. "Now he can only take the treatment and try his best to recover in Los Angeles.

"If he is fit enough he will run in the Eugene meeting," he added. "If not, he will have to pull out. The fundamental thing is to ensure he does not get any injuries."

Along with basketball player Yao Ming, Liu is China's best-known sportsman and the opening ceremony and high hurdles are the most highly-anticipated events of the Games for many Chinese.

Sun had earlier tried to play down the problem, saying Liu's withdrawal in New York had been precautionary.

"It's an overstatement to call it an injury," Sun told Titan sports newspaper this week. "His legs move and he would have easily raced within 13.20 seconds had he entered."

Liu ran a world record 12.88 seconds in Lausanne in 2006 but has not managed a time below 13 seconds in competition this year. His time of 13.18 in the final of the Olympic test event in Beijing last month was the fourth best time of the season.

(Agencies via Shanghai Daily June 5, 2008)