The U.S. ran without top 400-meter runner LaShawn Merritt, who pulled out of the Olympics during qualifying rounds last week.

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After gold-medal favorite LaShawn Merritt pulled a hamstring in Saturday's preliminaries, Tony McQuay and Bryshon Nellum took to the track Sunday for their semifinal heats.

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Beijing Olympic gold medalist LaShawn Merritt won the men's 400 in 44:32, and Jamaican Nickel Ashmeade ran the 200 in 20:14 to best Walter Dix in 20:16.

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LaShawn Merritt set a personal best of 44.14 in third.

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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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