Asafa Powell ruled out of 100 metres at World Championships

Asafa Powell, the fastest man in the world this year, was today ruled out of the 100metres at the World Championships in Daegu due to a groin injury but hopes to run in the relay.

The 28-year-old Jamaican won bronze at the 2009 worlds in Berlin and had been expected to be one of the main challengers to defending champion and compatriot Usain Bolt.

But he will not line up when the heats start on Saturday because of the injury, which forced him to miss the Diamond League meeting at Crystal Palace three weeks ago.

The news was revealed by his agent Paul Doyle, who believes Powell could recover in time for the 4x100m relay, which is a week on Sunday, the final day of the championships.

"The groin strain is still lingering," said Doyle. "He is not quite 100 per cent. The day after he runs, it is still very sore.

"Asafa is very disappointed to say the least. He was hoping to be able to run in what was going to be one of the most anticipated races of the championships. He's still optimistic to be able to run the relay."

Former world record holder Powell clocked 9.78sec in Lausanne in June, which is a tenth of a second quicker than Bolt's best this year.

Powell's absence means Bolt looks odds-on to retain his title as four of the five athletes above him in the 2011 world rankings are now absent - Tyson Gay has a hip injury while Steve Mullings and Mike Rodgers are banned after failing drugs tests. Trinidad's Richard Thompson will be the fastest man this year in the field after setting a national record of 9.85sec this month.

Bolt's 2010 was ruined by back problems which is why he is some way off the form which saw him win the title in a world record 9.58sec in 2009.

"This for me is a comeback season," he said. "I need to get back to tip-top condition, I don't think I'm in 9.5 shape at the moment. A lot of guys are running fast, I'm not in tip-top shape but I'm focused and ready."