New Zealand took a 4-0 lead over Britain in their America's Cup defence on Monday, with the crews locked in a tight early tacking duel and close passes in the first downwind leg before the New Zealand boat took control to win the race.
The New Zealand crew ultimately managed to get slightly more performance out of their AC75 monohull Taihoro, piling the pressure on Britain during the closest race so far in the first-to-seven-wins series against Ben Ainslie's Britannia.
Ainslie's British team, who were still smarting from an umpire's decision that went against them on Sunday in the pre-start, protested against the New Zealanders during a series of close crosses as the boats sped downwind.
"We are going to keep going and push all the way here, we can still come back from this," Ainslie said on the America's Cup live broadcast after Monday's single scheduled race.
He said that a reserve day on Tuesday would give the crew a good opportunity to work on ways to narrow the "click" in performance gap they were seeing against New Zealand's boat.
Ainslie's co-helm Dylan Fletcher said he was disappointed by the umpires' decision on Sunday, but the team would "take a good look" and see where they could eke out the gains needed to win.
New Zealand's ever-relaxed skipper Peter Burling said every win on the board was "a super nice one," adding that it had felt far more like a "boat race" on Monday than it had the day before, when he expressed concern over a pre-start near crash.
"We've made a step forward with the performance of the boat," New Zealand's co-helm Nathan Outteridge said of their foiling AC75, which is manoeuvring cleanly and at speed.