Team New Zealand capitalised on technical problems on board Luna Rossa to taste victory in their first race at the America's Cup preliminary regatta in Barcelona.
The Italian syndicate were forced to retire, sending the New Zealanders to the top of the standings after day one of the four-day regatta which leads into the start of the America's Cup proper next week.
Cup defenders Team New Zealand and the five challengers are racing their AC75 monohulls against each other for the first team, adding a level of intrigue to the round-robin regatta, which will finish with a match-racing final between the top two qualifiers on Sunday.
It was shaping as a close contest between the 2021 Cup Match finalists in Auckland, before Luna Rossa struck electrical problems and splashed down off their foils on the first leg before pulling out soon afterwards.
Team NZ's boat Taihoro emerged well from a tense pre-start and skipper Peter Burling was satisfied with their opening salvo.
"We've had some great practice racing against Luna Rossa and it was shaping up to really good race today," Burling said.
"So it was a real shame they had the issue with the boat and couldn't carry on because we felt that we had jumped out to a nice little lead there half way up the first beat and were looking forward to some good racing."
Luna Rossa helmsman Jimmy Spithill said their fault would be closely analysed.
"It was a shame as we had a good head-to-head race going with the Kiwis and it looked like it was going to be a good one," he said.
"We were disappointed not to get that race in but in a lot of ways we'd rather that sort of stuff happens now rather than when it really counts."
Luna Rossa bounced back to beat French syndicate Orient Express in a second race for both of those syndicates.
In other results, Swiss outfit Alinghi Red Bull beat Orient Express while American Magic beat Ineos Britannia.
Team NZ are scheduled to race twice on Friday night, against two winless opponents - Britannia and Orient Express.