Usain Bolt smashed his own world record in winning the Olympic 100 meters title in Beijing with one of the most remarkable performances in the history of track and field.

    The 21-year-old Jamaican clocked 9.69 seconds to win from Trinidad and Tobago's Richard Thompson (9.89 seconds) and America's Walter Dix (9.91 seconds).

    But it was the manner of his victory that was truly astonishing as he started his celebrations before crossing the line, showboating with his arms out wide before slapping his chest in triumph.

    He was still comfortably inside his own world mark of 9.72 seconds set in New York in May when he came to worldwide prominence as a gold medal contender.

    Bolt's great Jamaican rival and former world record holder Asafa Powell finished a disappointing fifth while America's world champion Tyson Gay failed to make the final as he finished fifth in the earlier semifinal round.

    Bolt, who will now be hot favorite to complete the 100-200 double, told BBC Sport that he expected to break his own record.

    "I felt the world record might go as it's a new track and very quick," he said.

    "I came here just to win and I did just that. I didn't even know I'd broken the world record until I did my victory lap.

    "Now I'm just concentrating on my two races coming up. I came here prepared and I'm going to try and do it the (100 and 200m double)."

    The race had been one of the most eagerly anticipated in sprint history, as record six of the eight finalists dipped below the magic 10 seconds barrier in the 91,000-capacity National Stadium.

    Powell, who again flattered to deceive on the big stage, was generous in his verdict on compatriot Bolt's performance.

    "Usain was spectacular," Powell told Associated Press.

    "He was definitely untouchable tonight. He could have gone a lot faster if he had run straight through the line."

    Earlier, walker Valeriy Borchin held off former champion Jefferson Perez of Ecuador to earn Russia's first athletics gold of the Beijing Games.

    Borchin won the men's 20 kilometers race walk in one hour, 19 minutes and 01 seconds for Russia's first Olympic walking success.

    The 22-year-old, who served a one-year drugs ban in the 2005/06 season, came home ahead 1996 Olympic champion Perez by 14 seconds, with Australian Jared Tallent a further 27 seconds adrift in the bronze medal position.

    Moments before Bolt's triumph Nataliia Dobrynska won the heptathlon in a one-two for Ukraine.

    The 2004 world indoor champion could afford to finish last in her 800 meters race, but had already earned enough points to hold off Lydumila Blonska, who served a two-year doping ban before coming back to take silver at last year's world championships.

    Hyleas Fountain of the United States took bronze.