The boss of America's Cup challenger Luna Rossa has called out the design of the boats, saying if Team New Zealand had listened to him, there would be more challengers.
The attack comes as the last of the serious contenders launched their boats over the weekend.
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Luna Rossa's America's Cup boat was launched in true Italian style. The slick lines of the AC75 was matched by the slick lines of their boss, who's blasted the design rules.
Patrizio Bertelli says they make the boats overly aggressive and too expensive. He told an Italian newspaper: "If the New Zealanders had listened to me, now we would surely have a greater number of challenging teams."
The radical foiling monohulls use cutting-edge technology and the $100 million price tag has put a lot of other teams off.
Only four challengers will compete in Auckland in 2021. One of them is INEOS Team UK, which also launched their boat, Britannia, over the weekend.
However the most successful Olympic sailor of all time, Sir Ben Ainslie, has no doubt racing will be spectacular.
"If you're a fan of technology and sport then this America's Cup will blow people away in terms of the scale and power of the boats," he says.
American Magic - out of the New York Yacht Club - is the most advanced challenger. Their boat Defiance is already up and foiling.
In terms of design, all four boats are markedly different from the hull to the size and shape of the foils.
"For anyone to predict right now which team has the tech edge, they'd be foolhardy," says America's Cup commentator Tom Ehman.
But Team New Zealand do hold a slight advantage being the first to launch and they're testing on the Waitemata where racing will be held.
A spokesperson said they know they've got a "long hard slog for the next 18 months".
A long hard slog that will hopefully end in glory.
Newshub.
