WORLD ATHLETICS CHAMPIONSHIP: Bolt wins 100m gold in Beijing

Jamaican Usain Bolt won the 100 metres title at the World Athletics Championships in Beijing, crossing the line in 9.79 seconds to reassert his status as the fastest man on the planet.

American Justin Gatlin, the form sprinter of the last two years, finished second in 9.80 to take silver, while Andre de Grasse of Canada and American Trayvon Bromell crossed the line together in third place in a time of 9.92.

Bolt, the reigning Olympic champion has now not been beaten in the 100m or 200m in six major global championships going back to 2007, although he was disqualified from the shorter race at the Deagu world championships in 2011.

The 29-year-old will go for successive world championship sprint sweeps in Beijing, the site of his breakthrough triumph at the 2008 Olympics, with the 200 metres final scheduled for Thursday.

Bolt will be a popular winner of the world title for a third time coming against Galtin, a figure who has twice served a drugs ban despite winning the 100m Olympic title himself in 2004.

"I understand why (people wanted him to win), but I wanted to do it for myself. It is a big deal," said Bolt.

Bolt won the race on the line with a frantic dip after reeling in the American in the closing 30 metres of a tension-packed race.

Bolt had been unfancied to claim victory after struggling with injuries over the past year with Gatlin entering the race as the man in form with the best form and times.

The defending world champion Bolt was left shaking his head in the semi-finals after powering back from his early shock of almost stumbling and falling to reach the final alongside Andre De Grasse of Canada, who clocked the same time.

Gatlin appeared to run well within himself in producing a run of 9.77 in the second semi-final to justify his standing with the bookmakers, but lost form at the vital time in the final in finishing second in 9.80secs.