London: France engineered an epic upset in the men's 4x100m freestyle relay, one of two French golds on a pulsating night of action in the Olympic pool where two world records fell.

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Yannick Agnel powered past American star Ryan Lochte on the final 50m of the closing relay leg as France won the coveted 4x100m relay gold for the first time in 3min 09.93sec yesterday.

The Americans' second-placed finish gave Michael Phelps a first career silver medal to go with his 14 gold and two bronze.

Russia took bronze over a stunned Australia, whose vaunted James "The Missile" Magnussen and James "The Rocket" Roberts failed to fire.

The victory was redemption of a sort for France, who went into the same race as favorites in Beijing four years ago only to see veteran Jason Lezak's miraculous final-leg swim deliver victory to the United States and keep Phelps' bid for eight gold medals alive.

The win was also part of a French festival at the Aquatics Centre, where Camille Muffat won the women's 400m freestyle in an Olympic record of 4:01.45.

American Allison Schmitt was second in 4:01.77 and 2008 Olympic champion Rebecca Adlington of Britain stormed home in lane eight for bronze in 4:03.01 to the deafening cheers of the home crowd.

American Dana Vollmer opened the action with a 100m butterfly triumph in a world record of 55.98sec, becoming the first woman to dip under 56 seconds in the event.

Cameron van der Burgh followed with an emotional world record-setting triumph in the 100m breaststroke, which he dedicated to late training partner Alexander Dale Oen of Norway.

Van der Burgh led from start to finish, winning in 58.46sec to improve on the previous world mark of 58.58sec held by Australian Brenton Rickard.

"If there is such a thing as the perfect race, I think I swam it at the right time tonight," said van der Burgh, who became the first South African man to win an individual Olympic swimming gold.

He said it was the gold, and not the record, that mattered most.

"I don't really care about the world record," said van der Burgh, who finished ahead of Australian Christian Sprenger and American Brendan Hansen.

"Once you have become an Olympic champion that can never be taken away from you."

But van der Burgh's joy was tempered by his memories of Dale Oen, who was at an Arizona training camp in April when he died of heart failure as the result of a blood clot.

He said his parents had been sitting with the Norwegian swimmer's parents at the Games.

"There is not much you can say to them, but I'd just like to celebrate the guy's life by winning a gold medal," he said.

Japanese breaststroke king Kosuke Kitajima's bid to become the first man to win the same Olympic swimming event at three straight games evaporated in the blistering pace set by van der Burgh.

"It was a really tough race and I needed the world record to win. I didn't have the ability to be honest," admitted Kitajima, who completed 100m-200m breaststroke doubles in Athens and Beijing and will try again for a treble in the 200m event.

South Africa's only other men's swimming gold came in the 2004 4x100m freestyle relay, making them part of the exclusive club of nations to beat the United States in the event along with Australia and, now, France.

(Agencies)

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