Bolt starts his quest in style

World's fastest man jogs to victory while Ohuruogu is just too quick off the blocks

Before settling into her starting blocks in the third of the first round women's 400m heats on the opening day of the World Championships yesterday, Christine Ohuruogu was heard to ponder in a pre-recorded interview: "There's a lot of unfinished business for me in the 400m. There's so much that I feel I've got to learn."

One thing Usain Bolt has been struggling to learn on the comeback trail following injury this summer is to get out of his starting blocks on what the sprinting fraternity like to call the "b" of "bang" He did so to such good effect in his first round 100m heat yesterday, he could affordto jog the last 50m, diverting his gaze to check out his form on the giant screen, and still clock the fastest time of the day.

It was a 10.10sec trot into a headwind that said the Lightning Bolt was back to something heading in the direction of his phenomenal best. On this evidence, had Tyson Gay and Asafa Powell not been on the injured list, they would have probably stood about as much chance of stopping Bolt in the final today as Ohuruogu now has of regaining the 400m crown that she claimed in Osaka in 2007.

Were it not for the 4 x 400m relay, Britain's only reigning Olympic track and field champion would be heading back to Blighty today after leaving all of her business sadly unfinished in the individual 400m on the Daegu Stadium track. In attempting to get away before even the "b" of "bang", Ohuruogu achieved something as rare as a 9.58sec clocking in the 100m: a false start disqualification in a major 400m race.

Clutching her hands to her face as the recall gun fired, she knew the red card was coming before the South Korean official arrived with it and ushered her to trackside, where she watched the race get under way at the second time of asking with a look of stunned disbelief. "Of all the people it could have happened to, it had to be me," Ohuruogu lamented later. "It's just so ironic. I can't believe it... I'm broken."

With that, the 28-year-old Londoner broke into tears. Having struggled to regain her old form after rupturing a quadriceps muscle, Ohuruogu was never likely to feature in the medal mix in Daegu. Had she not jumped the gun in such nervy fashion, however, she would have only needed to better 52.23sec to make it through to today's semi-final stage – as both of her Great Britain team-mates, Lee McConnell and Nicola Sanders, both safely managed to do.

"It was just a complete lack of focus," Michael Johnson, holder of the men's 400m world record, said. "In all honesty, you never know what you're going to get with Christine."

It was a basic error that even the schoolboy novice running in the preliminary round of the men's 100m managed to avoid. Blessed with the build of a hammer thrower, and with no previous 100m time to his name, Sogelau Tuvalu, a 17-year-old high school student from American Samoa, climbed out of his blocks with all the snap of someone wriggling out of a manhole. The rest of the field had disappeared into the distance, but at least it was a valid start. The heavyweight sprint rookie trundled down the track in 15.66sec, finishing last by a margin of 4.24sec. "Thank God it's finished," he said.

Tuvala's reaction time in the blocks was a statuesque 0.269sec. Bolt's was a lightning 0.153sec. The Jamaican looked what he is: a class apart. While Bolt applied the brakes and admired the view, Dwain Chambers strained to claim second in 10.28sec. Harry Aikines-Aryeetey and Marlon Devonish, the other two British representatives, also advanced.

"I feel so happy, because I've been working hard on my start all season," Bolt said. "I'm just here to defend my title, and to show the world, 'Look, I'm still the best'."

The only medal-winning athletes on day one were all wearing Kenyan vests. In the women's marathon, Edna Kiplagat led a 1-2-3 in 2hr 28min 43sec. Kenya then celebrated a 1-2-3-4 in the women's 10,000m, Vivian Cheruiyotprevailing in 30min 48.98sec.

Today's key events

10am Men's 800m semis.

10.30am Men's 100m semis. The penultimate hurdle for Bolt.

11.30am Men's 10,000m final. Fly Mo's moment?

12.45am Men's 100m final. Bolt v the clock.

2am (Monday) Heptathlon 100m hurdles. Jessica Ennis on her marks.

3am Heptathlon high jump.