US decathlete Ashton Eaton celebrates after setting a new world record in the men's decathlon at the US Olympic athletics trials in Eugene, Oregon, June 23, 2012. [Photo/Agencie]

EUGENE, Oregon - Ashton Eaton set a glittering decathlon world record at the US Olympic trials on Saturday, riding the cheers of a thrilled home crowd to upstage a stellar cast of athletes.

The 24-year-old's total of 9,039 points in wet and cold conditions bettered the 2001 mark of Czech great Roman Sebrle by 13 points and capped an extraordinary meeting for the American, who had already set decathlon records for the 100 meters and long jump legs on Friday.

"It's like living an entire lifetime in two days," Eaton told reporters after capturing the record on his own training track in Eugene, Oregon. "To do the best that I possibly could in my world makes me pretty happy.

"I really, really would never pick another event. The decathlon is the best."

The world silver medallist will head to London in a powerful decathlon duo with runner-up and world champion Trey Hardee, but Olympic champion Bryan Clay's hopes of defending his title were shattered.

Clay found trouble in the 110 meters hurdles and discus legs of the 10-event competition to finish 12th.

Eaton fell two seconds off world record pace with a lap to go in the closing 1,500 meters, but was lifted by a cheering crowd in his hometown to a personal best of four minutes 14.48 seconds to secure the mark.

US decathlete Ashton Eaton sets a new world record as he crosses the finish line in the men's decathlon 1500m at the US Olympic athletics trials in Eugene, Oregon, June 23, 2012. [Photo/Agencie]

"I don't care what anyone says, there is magic here," he said of the University of Oregon's Hayward Field.

Eaton had targeted the world record but "figured it would be when I was 28 in 2016," he said. "So four years early."

Dawn Harper ensured she will defend her gold medal at London after winning the 100 hurdles with a time of 12.73 seconds.

"The crazy part was I cramped up two or three times before the race," she said after edging runner-up Kellie Wells and third-placed Lolo Jones.

As one of the top three finishers to qualify with the Olympic standard, Jones earned a shot at redemption at London, having crashed in the Beijing Games final four years ago when leading.

"I was filled with doubt and fear. It's been a constant uphill battle, and to have the confidence to get through this - I'm just thrilled, thrilled to have another shot," said Jones, who has been the subject of a major US marketing campaign.

World champion Carmelita Jeter stormed to victory in the women's 100 in 10.92 seconds to top Tianna Madison, who ran 10.97.

Third place was being reviewed after Jeneba Tarmoh and three-times world 200 champion Allyson Felix, Tarmoh's training mate, tied with a time of 11.068.

The trials continue through July 1.