Italy, guided by Jimmy Spithill, have beaten Tom Slingsby's US boat in the America's Cup battle between Australia's star helms.

Italy's Luna Rossa will now face Great Britain in the final of the Cup challenger series, after they recovered from a breakage with a convincing win over their US semi-final opponents, NYYC American Magic, on Thursday.

The Italian team prevailed 5-3 in the first-to-five Louis Vuitton Cup semis, after the British crew had ended Switzerland's challenge in Barcelona on Wednesday.

Britain clinched their semi-final over Switzerland in the America's Cup challenger series on Wednesday to secure a place in the Cup final starting on September 26.

The winner gets to take on America's Cup defenders New Zealand for the coveted "Auld Mug", which dates back to 1851 and is the oldest international sporting trophy.

There were celebrations on the water and ashore on the beach after Italy secured their place in the final, with Spithill's co-helm Francesco Bruni pumping his fists aboard the sleek, silver Italian AC75 after crossing the finish line.

Italy had suffered a dramatic breakage to their traveller track, a key part of their foiling monohull's rig, on Wednesday which needed an all-night effort to get it fixed.

"We are a super strong team, we all deserve this win ... It was not an easy night in the shed," Bruni said on the America's Cup live broadcast after finishing, referring to the vast hangar where the boats are housed.

Spithill dedicated the win -- which he described as "one hell of a fight" -- to Italy's boat builders.

"This victory really has to go to our shore team," he said, adding that when he went into the team's shed "it was like a bunch of zombies walking around".

For the United States, who suffered a setback when Slingsby's co-helm Paul Goodison fell down a hatch and broke five ribs, the America's Cup dream is over once again.

"A huge congratulations, the better team won," said Slingsby. "We knew we had a big fight on our hands, but we've got to hold our heads high."