Kiwi helmsman Dean Barker and his NYYC American Magic have crashed in spectacular fashion, as they seemed headed for victory in Prada Cup racing off Auckland.
With weather conditions in complete contrast to Saturday's light winds, America's Cup challengers struggled to deal with squalls on the Hauraki Gulf all afternoon, with race organisers having to abandon one race midway through and reset their course, after wind direction switched 90 degrees.
Desperate for their first point after three previous losses, the Americans seemed on course for victory against Luna Rossa Prada Pirelli in the day's second scheduled race, when disaster struck.
Rounding the final mark at high speed, the foiling AC75 monohull Patriot hit a huge gust of wind that sent it airborne and then crashing to the water, tipping over on its side.
A quick headcount showed everyone had survived the impact safely - they would have trained for such a contingency - and the Italians sailed away towards the finish-line. Their win was confirmed halfway down the course, when race officials declared the Americans had "retired".
"What a crazy race," declared Luna Rossa helmsman Jimmy Spithill over onboard comms.
Within minutes, the American Magic organisation tweeted to confirm everyone onboard was intact.
"Awful end to what was looking like a great race for Patriot," it said. "We have confirmed that all crew are safe."
Air bags were used to try to keep the boat afloat, as it threatened to sink, and Emirates Team NZ rushed to the scene to support their rivals.
Earlier in the day, Luna Rossa and Team UK had to abandon their opening race, when the northerly winds shifted and made the north-south racecourse marginal to sail.
After a delay, the race was resailed, with the British continuing their dramatic turnaround in form since the pre-Christmas world series, when they consistently struggled to finish.
Sir Ben Ainslie actually navigated his Britannia boat further around the course than counterparts Spithill and Francesco Bruni, but was consistently a couple of knots faster downwind, reaching a top speed of 46 knots.
Sunday's results complete the first two of four rounds of round-robin racing, with Team UK unbeaten and Luna Rossa achieving a two-win/two-loss record, both wins coming against the hapless Americans, who now face a massive job regrouping before next weekend.
Join us at 3pm Friday for live updates of the America's Cup challenger series