Phelps surpasses Spitz record

Phelps surpassed Mark Spitz's achievement at the Munich Olympics in 1972 by capping an astonishing performance over nine days of swimming with yet another world record - his eighth of the meet - in his final swim.

The American quartet - completed by Aaron Peirsol, Brendan Hansen and Jason Lezak - touched the wall in 3 minutes 29.34 seconds, 1.34 seconds under the world record and 0.70 secs ahead of Australia with Japan in third, while Great Britain finished sixth in a British record time of 3:33.69.

The 23-year-old Phelps played a key role in the Americans' win, hauling his team back into the lead after Kosuke Kitajima had given the Japanese the advantage at the halfway mark.

But a commanding display by Phelps gave the United States the advantage as Jason Lezak went head-to-head with 100m freestyle world-record holder Eamon Sullivan in the final leg, and he more than held on to give the Americans gold.

The win completed a golden meet for Phelps, who also won the 100m and 200m butterfly, the 200m and 400m individual medley and the 200m freestyle as well as being part of the relay teams which won the 4x200m freestyle and the 4x100m freestyle relay.

The men's relay result was a reversal of how the top two positions finished in the women's relay, with Australia taking gold ahead of the United States while Britain just missed out on a medal by finishing fourth.

Jessicah Schipper held off a determined challenge from Dara Torres of the United States on the final freestyle leg to hand the Australians the gold in a time of 3:52.69, more than three seconds under the old world record.

Grant Hackett's bid for an historic treble in the 1500m freestyle was ended by Tunisian Oussama Mellouli, who relegated the Australian to second place for the first time at the Olympics.

Britain's David Davies, who won bronze in this event in Athens in 2004, finished sixth and the Welshman's time of 14:52.11 was six seconds short of the time he recorded in Friday's heats.