Britain's world champion Shanaze Reade crashed out in a dramatic women's BMX final to shatter her Olympic dream.
Reade, 19, badly bruised her hand in the fall, finishing eighth, but an X-ray showed that there was no fracture.
French rider Anne-Caroline Chausson, in her final race, triumphed ahead of her compatriot Laetitia le Corguille with American Jill Kintner taking third.
Reade, who also fell in a semi-final heat, started well before Chausson
passed her on the first turn.
She was attempting to pass Chausson on the inside but clipped her back wheel and tumbled down.
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The Crewe teenager had suffered a heavy fall in the opening semi-final heat but recovered her composure by finishing second in the next and then clocked the fastest time in winning the third heat to reach the final.
"I put everything into this and I couldn't have done any more," said a bitterly disappointed Reade afterwards.
"I've fallen off and got back up, I've fallen off and got back up. I gave it my heart and everything, but today it wasn't good enough."
Her bid to overtake Chausson sent Reade sprawling from her bike and onto the track.
"I dug deep and gave it the best shot I could but today it wasn't good enough," she said.
"I'm 19 and there is more to come from me as an athlete but at the moment I'm hurting - my back is sore and I think I have broken my hand."
The BMX cycling event is making its debut at the Olympic Games and Reade, unbeaten all year, had been favourite to claim the women's title.
Her final crash was the Briton's third tumble from six rides at the Beijing Games.
British Cycling had paid out £30,000 to construct a replica of the Olympic BMX track in Manchester, across the road from its national headquarters.
Performance director Dave Brailsford wanted Reade to practice on the unusually high Olympic start ramp they have at Laoshan in the south west of Beijing.
The investment appeared to pay off as Reade started consistently better than any other rider but, having crashed twice there, it was the first bend which hurt her chances most.
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