The Unites States snatched victory from France in the 4x100m relay swimming final and dashed South African medal hopes in the process.

Australia's Eamon Sullivan set the tone setting a world record 47.24 for the first leg, with Michael Phelps and Lyndon Ferns clocking American and African records in 47.51 and 48.15 respectively. Only 0.91 seconds split the top five at the first changeover, as the US, France and Australia moved away, with South Africa dropping from fifth to seventh. Frederick Bousquet put France into the lead on the third leg and the gold seemed secure when Alain Bernard turned with over a body length lead for the final 50metres.

American Jason Lezak had a different opinion ? his powerful and determined clawing back of centimetres in the final quarter took him alongside Bernard and by slipping in an extra stroke, the American stole the touch for a world record 3:08:24.

Lezak, off a 0.04 reaction time, was clocked at and amazing 46.06 for his final leg.

The odds were stacked against South Africa, as both the US and France replaced three swimmers for the final. South Africa, had used their four fastest swimmers to get into the final and could only rotate the order putting Darian Townsend in second, and Ryk Neethling on the final leg.

"We did everything we could, we changed the order trying to get more front end speed," said Townsend. "We broke the African record Sunday and again this morning ? we're very proud of our team," he said.

The race highlighted the scale of improvement over the four year Olympic cycle. All eight finalists went under the World and Olympic record time set by South Africa in Athens, and the top six went under the subsequent record of 3:12:46 set by the US in 2006.

"It (the times) just shows how things have turned around in the last nine months. Our time would have won world champs nine months ago," said Neethling. "The world changed, we haven't changed fast enough with it ? we still have the same four guys from 2004, we didn't have any guys to look to, so we were always going to be up against it," he said.

The result leaves Team South Africa without a medal, and few finalists at the start of the third day of competition and will be a major disappointment to an expectant public.

"Everyone expected us to win a medal back home I guess. We never expected to win a medal, no-one in the world expected us to win a medal ? we came here to race and that's what we did," summed up Ferns, who has high hopes of further improving his time in the 100 freestyle and the possibility of a medal in the medley relay.

In the first semi of the men's 200m freestyle Jean Basson became South Africa's first individual finalist winning his race by over a second in one minute 46.13 seconds.

Turning at 50m in second spot, Basson took control passing Britain's Ross Davenport who was pushed to third by the charge of Russian Danila Izotov.

"I was hurting pretty bad in the second 100, but I've got more in the tank ? I'm much better prepared for this meet than I've ever been. I should do a best time," said Basson whose time ranked him third, 0.37 seconds behind Peter Vanderkaay and Taehwan Park.

Michael Phelps seemed content to finish third in the second semi in 1:46.28, using the race as a pipe-opener for his subsequent contribution to the US relay team.