Despite Ian Thorpe's five individual wins, the American team left Australia in their wake with 21 golds to their rivals' 11.

And they finished on the highest possible note when Aaron Peirsol, Brendan Hansen, Michael Phelps and Jason Lezak set a new world best in the 4x100m medley relay.

USA star performer Natalie Coughlin picked up her fourth medal at Yokohama in the final day's 4x200m relay and added a silver in the 4x100m medley.

Peirsol completed a 100m and 200m backstroke double before giving the USS a first-leg lead in the 4x100m medley.

A phenomenal third leg of butterfly from Phelps put them 0.37 seconds inside world record schedule.

Lezak had been caught by Thorpe on the anchor leg of the 4x100 freestyle on Saturday.

But this time he held off the Australian to bring the USA home in 3:33.48, eclipsing the old mark of 3:33.73, set by the Americans at the 2000 Sydney Olympics.

Phelps, touted as the American Thorpe, had twice came close to world records in the 200m and 400m individual medleys.

And he bounced back from a surprise 200m butterfly defeat by team-mate Tom Malchow to energise the US on the third leg of the 4x100m medley.

"We came here with a very, very strong team and very high goals," the 17-year-old said.

"As a whole, we stepped it up this week and I think we should ride this wave to the 2004 Olympics."