American LaShawn Merritt obliterated the field including defending champion Jeremy Wariner to win the Olympic men's 400 meters title on Thursday.

Merritt sealed a seventh straight gold in the event for the U.S., starting relatively slowly before blasting down the final straight to cross the line in a personal best of 43.75 seconds.

Wariner, visibly frustrated and distraught, finished a distant second in 44.74 seconds and David Neville took third with a spectacular dive for the line to complete a U.S. sweep of the medals.

The 24-year-old Wariner has dominated the 400m over the past four years but lost twice to Merritt this season, including at the U.S. Olympics [Images] trials.