US hit by second Hamm withdrawal

Hamm had already been given a cortisone injection to help him compete

American gymnast Morgan Hamm has pulled out of the Olympics after aggravating an ankle injury during training.

The 25-year-old has been struggling with the injury for a year and an awkward landing ended his Games hopes.

Morgan and his twin brother Paul helped the United States win their first gymnastic medals in 20 years in 2004.

But Paul withdrew with a broken hand in July, meaning his team has no gymnasts with Olympic experience, and Sasha Artemev or David Durante will step in.

Morgan is one of the best in the world in the floor exercise and one of the best American competitors on the pommel horse.

He said: "I am unable to perform my tumbling skills at the level that I need to.

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"This has an impact on my ability to contribute to the team's goals and by continuing I would be putting myself at further risk.

"There are two very capable athletes who can step in and help this team more than I can right now."

The twins are now expected to retire from the sport.