Britain's Michael Bingham finished third in the 400m behind American Jeremy Wariner, who won in 44.94.

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So we're talking about Jeremy Wariner, in the 400 meters, and he's got some strong competition this year.

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"They have been on my hips all season and today they just dug deep and ran well, " said Wariner.

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Wariner pulled up in the final metres of the 400m, clutching his right thigh and hobbling across the line in last place.

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Defending 400m champion Wariner , who was shocked by Merritt in Beijing last summer, progressed in 45.54 and Merritt impressed with a run of 45.23.

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American 400m runners Jeremy Wariner and Sanya Richards, as well as Ethiopia's Tirunesh Dibaba (5000m), all triumphed in their events to maintain their jackpot hopes.

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"With the likes of Jeremy Wariner in the field I couldn't ask for a stronger test, but these are the sort of challenges I want, " said Pistorius, 20.

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It was Wariner who had looked the likely winner at the mid-race stage before Benjamin and Washington made their moves, but Benjamin said the contact made no difference to the outcome.

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In the men's equivalent, Jeremy Wariner put his Olympic heartache to one side by gaining some sort of revenge over LaShawn Merritt, beating his American compatriot into second and therefore reversing the finishing order from the final in Beijing.

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