American Dawn Harper sprung a huge surprise when a dramatic mistake by compatriot Lolo Jones let her through to win Olympic gold in the women's 100 metres hurdles.
|LoLo Jones, right, makes a small but crucial mistake [AFP]
Jones, the fastest woman in the world this year, looked to be gliding to victory but clattered into the penultimate hurdle and Harper surged across the line to win her first major title.
The 24-year-old clocked 12.54 seconds but it needed a photo to separate the next four runners, who all finished within two hundredths of a second of each other.
After a couple of minutes wait, Australia's Sally McLellan was awarded silver and Canadian Priscilla Lopes-Schliep bronze with the same time of 12.64.
The 21-year-old McLellan and Lopes-Schliep, 25, squealed with delight and jumped up and down hugging each other when the result was flashed up on the screen.
American Damu Cherry and experienced Jamaican Delloreen Ennis-London, who finished fourth in Sydney eight years ago, were also awarded the same time of 12.65 for fourth and fifth place.
Jones, the world indoor sprint hurdles champion, stumbled over the line in seventh and remained crouching trackside for a long time trying to come to terms with what had happened.
The 26-year-old, who nearly gave up the sport after failing to get into the U.S. team for the Athens Olympics four years ago, ran the quickest time of the year in the heats and was favourite to win gold.