Beijing: Jamaica’s Usain Bolt scorched to Olympic 100 metres gold on Saturday, opening his arms wide in celebration 20 metres from the line before clocking a world record 9.69 seconds.

The 21-year-old claimed his country’s first Olympic title in the blue riband event and capped an astonishing rise to the top of his sport. His former world record was 9.72 seconds.

Richard Thompson of Trinidad and Tobago took the silver in 9.89 and American Walter Dix the bronze in 9.91.

Bolt’s time would have been even better if he had not looked around and pumped his arms with victory assured 20 metres from the line.

“I wasn’t bragging,” said Bolt after being mobbed by Jamaicans in the stands. “When I saw I wasn’t covered, I was just happy. I was always the fastest. I told you all I was going to be number one and I did just that.

“I wasn’t really worried about racing fast. My only aim was to be a champion.”

It was the first time the men’s 100 metres world record had been broken in the Olympic final since Canadian Donovan Bailey in 1996.

Jamaican Asafa Powell, whose world mark Bolt bettered in May, once again failed to deliver on the big stage and finished fifth.

“I messed up big time,” he told reporters. “My legs died on me. He was definitely untouchable tonight. Usain is spectacular. I’m very happy for him.”

World champion Tyson Gay of the US did not even make the final, finishing fifth in his semi-final to end hopes of a showdown between the three fastest men of all time.

The atmosphere was still crackling as the six Caribbean and two American athletes settled into the blocks.

At 6ft 5in , Bolt was never going to be the quickest of starters but he got away well enough and, head down, found his huge loping stride to hit the front after about 25 metres.

“I got a great start,” he said. “I was getting good starts all the way to the final. I was getting better and better, it was crazy, phenomenal.”

Bolt, a 200 metres specialist who had run only one professional race in the shorter distance before this year, will now turn his attention to becoming the first man since Carl Lewis in 1984 to win the Olympic sprint double.

Anxious to avoid the tougher training regime of the 400 metres, Bolt reached an agreement with his coach last year that if he broke the Jamaican 200m record he would be allowed to try the 100.

The reggae-loving Bolt duly delivered and ran an impressive 10.03 seconds in his first outing in Greece in July last year.

The world 200m silver medallist picked up where he left off with an identical time in his first outing of 2008 but his third run in Kingston was simply remarkable.

His time of 9.76 was then the second fastest in history and his coach Glen Mills reckoned he could have broken Powell’s record of 9.74 had he not turned to check on his rivals towards the end.

Better was yet to come. In New York on the last day of May, Bolt got off to a flyer and thundered down the track in 9.72 seconds. Jamaica had a new world record holder.

A keen cricketer before he turned to athletics, Bolt first announced his talent when he became the youngest world junior champion by winning the 200m in Kingston in 2002 at the age of 15.

Now, he will be remembered as the man who brought the first 100m gold to his island, which in Linford Christie, Donovan Bailey and the now disgraced Ben Johnson had produced three Olympic 100 metres champions for other countries.

Meanwhile Usain Bolt’s father when contacted at home in Kingston after Bolt's sprint of glory remarked that Bolt streaked to 100 metres Olympic gold thanks to yam power.

Wellesley Bolt said his son was partial to the vegetable grown in the north-western area of Jamaica where the sprinter was born.

“It is definitely the Trelawny yam,” Bolt senior said seconds after his son smashed the world record on the way to landing the biggest gold medal in sport.

“I was very nervous before the race, my heart was pumping. I spoke to him about two days ago and told him that I was getting nervous and he said ‘don’t worry Dad, I am going to win this one for you’,” Wellesley said, speaking from his home, less than 30 minutes drive from the western tourist city of Montego Bay.

“My house has been taken over by more than 100 people from inside and outside the community.

“They are waving flags, beating drums and just making a lot of noise. But this is a special moment and to know that a Jamaican has done this and I am the father of that Jamaican makes me feel special.”