Chinese hurdler Liu Xiang is recovering after an operation to repair his right Achilles tendon at the private Wellington Hospital in London.

Chinese hurdler Liu Xiang is recovering after an operation to repair his right Achilles tendon at the private Wellington Hospital in London.

Li Yuyi, head of the Shanghai Sports Bureau, told Xinhua news agency that Thursday's surgery took 79 minutes and doctors were optimistic about the outcome.

Liu will stay in the hospital for two or three days before returning to Shanghai.

The athlete would need at least four weeks to recover, a Chinese doctor said.

Liu's London Games ended when he clattered into the first hurdle during his 110m heat on Tuesday, four years after he had to withdraw from the Beijing Olympics because of a tendon injury.

When it was confirmed that the 2004 Olympic champion had ruptured his tendon, the Chinese delegation contacted local medical organizations to find the best hospital and the best surgeon for Liu, China's athletics team leader Feng Shuyong said.

Du Zhaocai, vice chairman of the Chinese Athletics Association, said Liu's doctor was an expert in sports medicine and had operated on many famous athletes, including David Beckham.

Liu, 29, earned a rousing ovation from the 80,000 crowd in the Olympic stadium on Tuesday as he hopped down the track to cross the finish line, kissing the last hurdle on his way.

In his absence, American Aries Merritt won gold on Wednesday after Cuba's Dayron Robles also suffered an injury, tearing his hamstring.