'I need time', says distraught Bolt

Speaking about the defence of his 200m title, which begins on Friday, he said: "How will I go? It's on a Friday right? Then we'll have to see on Friday."

Following his brief statement he left for the athletes' village by car.

Athletics governing body, the IAAF, said it was disappointed that Bolt had false-started but that a sport's credibility depended on its rules and they had to be applied consistently and fairly for all athletes.

Blake admitted to mixed feelings following his unexpected win.

"I can't find words to explain it. Usain Bolt has been there for me. I feel like I want to cry," said Blake, Bolt's training partner under coach Glen Mills.

"I've been trained by one of the best coaches but I stayed cool and caught him (Collins). I felt I would win the race for Bolt."

Bolt, the most marketable sportsman on the globe, has dominated the sprinting world in recent years and was widely expected to add to his burgeoning collection of gold medals.

After storming to the 100m and 200m sprint double in then-world record times at the 2008 Olympics, Bolt matched his feat the following year at the Berlin worlds, setting new marks of 9.58 and 19.19sec.

"It's surreal," said silver medallist Dix said of Bolt's disqualification.

"It's great to put the US back to the medals stand but it was a terrible race for me.

"It was a sloppy race. It was nerve-breaking. I didn't really think they would kick him out (Bolt)."

Veteran Collins, who won 100m gold at the world championships in Paris in 2003, said: "It was awesome. I got out well and it was a great race. I didn't think they would catch me.

"The champion is out and you have to take advantage of it," said the 35-year-old. "However, maybe if he had still been there I would have (got a medal).

"I don't think the false start rule is the right one but as the IAAF think it is good for TV it will probably stay. I know what I can do to make it to London next year."

The event in Daegu was deprived of the three fastest men this year before the championships started -- Bolt's team-mate Asafa Powell, American Tyson Gay, and Jamaican Steve Mullings.