Double world champion Tyson Gay and a host of the world's leading performers will be vying for coveted Olympic spots at the United States selection trials which start today.

A strict format that allows only the top-three finishers per event to qualify for Beijing leaves open the possibility of major upsets at the 10-day meet, but the US team will still head to China confident of completing an impressive medal haul.

"This will be our best Olympic Games... men and women," US Olympic women's coach Jeanette Bolden told reporters after surveying the field for the trials.

"It will have a nice mixture of both veteran and up-and-coming athletes."

Gay, Olympic and world 400 metres gold medallist Jeremey Wariner, women's 200 metres world champion Allyson Felix and 400 metres favourite Sanya Richards are all expected to shine on the University of Oregon's Hayward Field track.

The women's 100 metres with Felix and former world champions Lauryn Williams and Torri Edwards is likely to be just one of many intense and classy encounters.

If the favourites survive the trials, American athletes could head to Beijing for the August Games confident of sweeping Olympic medals in both the men's shot put and 400 metres hurdles.

"It's brutal," said two-time Olympic shot put silver medallist Adam Nelson, who will be challenged by world champion Reese Hoffa and indoor winner Christian Cantwell.

The double bid of world 1,500 and 5,000 metres champion Bernard Lagat is also an interesting prospect. Twice an Olympic 1,500 metres medallist for his native Kenya, Lagat will be aiming for his first Games in a US vest, having become an American citizen in 2004.

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.