The 25-year-old from Montfermeil, world champion in the vault in 2010 and one of France's top medal hopes, said in a statement that the leg had been successfully operated upon.

"He slipped from the bar in what was a very simple move. It's almost inexplicable and even he doesn't know why it happened," Laurent Guelzec, the coach of the French men's team, said.

"He is in a state of shock.

"It's a serious injury, the ligaments in the knee are damaged."

Bouhail's brother and agent, Mickael, said it would be at least two months before a decision could be made on his participation in London.

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