Bolt needs short burst to make final 

Source: ReutersJamaican sprinter Usain Bolt

Triple Olympic champion and world record holder Usain Bolt breezed into the world championship 200 metres final on Thursday, needing only an opening 30-metre burst to establish his dominance in the semi-final.

The Jamaican was in no mood for pre-race showboating, quickly carving out a lead before easing off in the straight and trotting over the finish line with the best overall time of 20.08 seconds.

He was quickly back to his usual self after the race, throwing his vest into a group of cheering girls.

American Shawn Crawford, who won silver at the Beijing Olympics behind Bolt, had to work hard to come in third following Panama's Alonso Edward who clocked 20.22.

The 19-year-old Edward has run the fourth best time this season of 20 seconds flat and, with American world champion Tyson Gay injured, could be in medal contention come Thursday's final.

"The guy is phenomenal," said Crawford of Bolt. "I think the final is going to be fast. He is looking very impressive right now. If he stays with it he will run probably 19.20."

Crawford, who made a chopping move before his heat, said he was preparing to slay dragon Bolt.

"Yesterday I said I was the dragon slayer and the only way I am going to slay my dragon is to cut his head off."

"I am going to try to get away with it. If I can trip him without getting caught. The cameras make it hard to get away with it," Crawford said.

American Wallace Spearmon, who lost his Beijing Games bronze medal after stepping out of his lane, was untroubled, comfortably winning his heat with 20.14, joined by Jamaican Steve Mullings.

Mullings, banned for doping for two years before resuming his sprinting career in 2006, was impressive in the first 100 before easing off to finish just ahead of American Charles Clark and Ramil Guliyev from Azerbaijan who both also went through.