Powell has run under 10 seconds 12 times this season

The Jamaican, 23, was pushed hard by American Leonard Scott but closed him down over the final few metres to win in a championship record 9.89 seconds.

Olympic champion Jeremy Wariner also kept up his 100% record in the 400m.

It was a bad day for Britons Mo Farah (3,000m) and Kelly Sotherton (long jump), who came last in their events.

Interview: 100m world record holder Asafa Powell

Interview: British heptathlete Kelly Sotherton

Powell's victory in Stuttgart was his 23rd straight win and his 12th legal sub-10 second run in 2006.

"This is the last real race for me this season and I ran 9.89, so I'm really happy about that," Powell said.

"I want to win a major championship next season and I am working towards that now."

Scott finished a close second to Powell in a personal best 9.91 with compatriot Tyson Gay third in 9.92.

Wariner was also not at his dominant best in the 400m as he was forced to hold off Congo's Gary Kikaya.

It was tough out there because they are the best in the world Mo Farah

The American edged him out in 44.02 while Kikaya set a new African record of 44.10 for second. LaShawn Merritt set a personal best of 44.14 in third.

"They have been on my hips all season and today they just dug deep and ran well," said Wariner.

"I just stayed focused through the line. I wanted to run under 44, but it just gives me something to focus on next year."

Farah struggled to cope with a world-class field in the men's 3,000m, where he was the only European representative.

The European 5,000m silver medallist, 23, paid the price for a brave display of front running and he trailed home in last place in eight minutes, 00.60 seconds.

Kenenisa Bekele's brother Tariku took a deserved win in 7:38.98 ahead of Kenyans Edwin Soi and Isaac Songok.

"It was tough out there because they are the best in the world and I was just lucky to be in the race," said Farah.

"I was really tired out there and when I hit the front there was nothing there at all.

"But I can't complain this season as it has been going really well for me."

Commonwealth silver medallist Tasha Danvers-Smith was the best of the Brits as she came home fifth behind race-winner and world number one Lashinda Demus in the 400m hurdles.

"I wasn't up against against a bunch of pansies out there, they're the best in the world," said Danvers-Smith. "So that wasn't too bad."

Heptathlete Sotherton was given a wildcard to contest the long jump but she finished last after only managing to land one legal jump of 5.85m.

European triple jump champion Tatyana Lebedeva took top spot with a best effort of 6.92m.

Becky Lyne, the European 800m bronze medallist and Jo Pavey (3,000m) carry British hopes on day two in Stuttgart.

Those that finish on the podium take home $30,000 (�16,079), $20,000 and $12,000 respectively with a $100,000 bonus for any athlete breaking a world record.