Beijing Olympic champion Dayron Robles is troubled with injury, leaving open the title of men's 110m hurdles at Berlin world athletics championships.

Earlier on Wednesday morning, Robles had a narrow escape into the hurdles semifinals with 13.67s, but then stated a thigh-muscle injury and said he was far from certain to return to the track on Thursday.

"I have trouble with my left leg. I can't say whether I can run tomorrow or not. I will work hard with my doctors. We will then see what is possible," the world record holder said.

If Robles can't go on, it would make the event wide open as 2005 champion Ladji Doucoure of France and 2007 winner Liu Xiang of China are also not in Berlin for injury reasons.

American Terrence Trammell, who advanced with 13.51s, could finally get a gold after two runner-up spots each from worlds and Olympics in the past.

"I needed to get the kinks out. After two silvers my focus is on the gold medal," said Trammell.

Compatriot David Payne, who has silver from the 2008 Olympics and bronze from the 2007 worlds, also advanced with 13.54 seconds, while Hungary's Daniel Kiss led the heats with 13.34 seconds.

(Xinhua News Agency August 20, 2009)