BEIJING — Melaine Walker of Jamaica has won the gold medal in the women's 400-meter hurdles in an Olympic record.

Walker won in 52.64 seconds in Wednesday's final, with Sheena Tosta of the United States taking silver in 53.70 and Tasha Danvers of Britain third in 53.84.

Walker's win came minutes after her countryman Usain Bolt completed a sprint double by winning the men's 200 in world-record time.

The hurdles final was wide open with world record-holder Yulia Pechonkina skipping the Olympics because of a heart problem, two-time world champion Jana Rawlinson out injured and reigning Olympic champion Fani Halkia expelled after testing positive for a steroid.