BEIJING - Liu Xiang is targeting a September return to competition, his coach was quoted as saying Wednesday, ruling out the likelihood of the Chinese hurdler attempting to defend his world championship title.

The 2004 Athens Olympic gold medallist has resumed training after surgery on his right foot in December at Houston, Texas.

His longtime coach Sun Haiping was quoted as saying in Wednesday's China Daily newspaper that Liu would not begin training in running spikes until the heel had entirely recovered.

A medical exam scheduled for the end of the month will allow a progress update, but Sun said the earliest Liu would return to competition would be at the Shanghai Golden Grand Prix event in September. The world championships are at Berlin in August.

"All our efforts are to get Liu back to normal, so we won't push him hard to take part in competition,'' Sun said.

The injury kept him from defending his 110-metre hurdles title at last summer's Beijing Games, where he sensationally withdrew at the start line in the heats. He was China's best hope to win a gold medal in athletics at Beijing.

Liu set a world record of 12.88 seconds for the event in 2005 but Cuba's Dayron Robles lowered the mark to 12.87 last year, and also won gold at the Beijing Olympics.

Sun has expressed doubts as to whether Liu will ever regain his peak speed, and the 25-year-old Liu himself says he'll retire if he is injured again.

Despite that, Liu remains one of the most popular and best paid athletes in China, with numerous lucrative endorsement deals.