Cannot play media. Sorry, this media is not available in your territory.
Video - Lolo loses out as Harper hurdles home
American Dawn Harper took advantage of a mistake from favourite Lolo Jones to win the women's 100m hurdles final.
Jones, also from the US, was clearly leading after 80m but clipped the penultimate barrier to let in Harper who claimed victory in 12.54 seconds.
Australia's Sally McLellan, who had a great start, took silver and Canada's Priscilla Lopes-Schliep claimed bronze.
Britain's Sarah Claxton finished eighth, while Jones collapsed to the floor in disappointment ending seventh.
Jones described the moment it went wrong for her in the race.
"At the middle part of the race the hurdles came up very fast," the American said.
"I wanted to keep things tight. It was like racing a car at high velocity. When you hit a curve, you either maintain control of it or you crash and burn. Today I crashed and burned."
She added: "Today is hard. Tomorrow will be harder. I just have to get myself back up."