America's Cup champion in practice capsize

Oracle Team USA have capsized their catamaran for the second time in a month as they prepare for an America's Cup defence.

America's Cup champion Oracle Team USA capsized its 50-foot catamaran during a practice session. (AAP)

Two-time America's Cup champion Oracle Team USA capsized its 50-foot catamaran during a practice session Wednesday on the Great Sound.

The team said there were no injuries and that damage appeared to be limited.

With help from support boats, the catamaran was righted just three minute after rolling over onto its port hull.

It was Oracle's second capsize in a month.

The America's Cup trials begin on May 26.

The 35th America's Cup match begins June 17 between Oracle and the winner of the challenger series.