Olympic gold medalist hurdler Liu Xiang will retire if he is dealt another serious injury like the one that forced him to withdraw from the Beijing Games, the Chinese pin-up said over the weekend.

"If I get injured again, I will say goodbye to the sport," the 26-year-old Shanghai native said. "Even if I had not suffered this (Achilles) injury, I planned on retiring around 30It's impossible to be an athlete your whole life."

The Athens Olympic champion was dealt a cruel blow last August when his leg played up during the preliminary rounds of competition leaving him unable to defend his Olympic crown on home soil.

Liu, still the reigning world champion, is reportedly able to train unaided right now after having surgery in Houston in December. American doctor Tom Clanton has given him the green light to fly back to China after marveling at his speedy return to fitness.

But doubts remain as to whether the nation's top track and field star has time to hit his peak in time for the upcoming IAAF World Championships. Others claim he lacks the longevity to stay strong until London 2012, when he will be 29.

Liu is aware of the challenges ahead but said he is undaunted.

"At least I can live life as a normal person," he said, joking. "I know there's a long way to go before I get back to my best, but I'm not afraid of a challenge. I will try to keep calm. I'm even considering what to do in the worst-case scenario (of getting injured again) so I don't feel under too much pressure."

Coach Sun Haiping said that Liu has started running slowly and training over hurdles but he still has much ground to cover physically and mentally.

"Right now, he is 60 to 70 percent recovered. I don't think it will be difficult for him to get back to 90 percent fitness.

"The most difficult step is the last 10 percent. It requires high-intensity movement, power and speed. I cannot predict (if or when he will hit his perfect stride). We will wait and see what happens after he comes back home."

Sun also expressed concern about whether Liu would be able to rediscover his mental resilience and discard his injury fears.

"I'm afraid even if he is fit physically, he will be distracted by the fear of getting injured again. It takes some time to overcome (that)," he said.

"He was a top-level athlete before the injury, but now his training has been badly affected and it will be difficult to run those best times again.

"If he suffered another injury, I don't think there would be any point continuing his career."

Who will take over?

Liu is the first Chinese male athlete to win a gold medal in track and field at an Olympics and World Championships, a feat that has pundits now wondering who will pick up the mantle as his successor.

Shi Dongpeng has long partnered Liu at the 110m hurdles and the 25-year-old boasts a personal best of 13.19 seconds. Liu set a (since eclipsed) world record of 12.88 seconds in July 2006 and won Olympic gold two years previously in 12.91, meaning that Shi is still deeply in his shadow.

Critics say this has hampered the younger athlete's growth, as he only performs well alongside Liu despite having the experience of three World Championships and two Olympics under his belt.

Shi's status as China's No 2 in the sport is also under threat following his loss at a recent 60m domestic competition. Attention is being focused on homegrown rivals Yin Jing, 21, and 19-year-old Xie Wenjun.

Xie, who is also coached by Sun Haiping, won the national championships last year and has far from exhausted his potential.

Meanwhile Yin, who has already beaten Shi in domestic competition, was dubbed the "most likely person to follow in Liu's steps" by the star's coach.

Yet Sun cautioned that Liu's achievements should not be belittled nor his footsteps considered easy to follow.

"Liu's success comes mostly from his technique and rhythm," he said. "It's not easy to do what he has done. Liu is a rare talent."

Source: China Daily