Sailing-British chase America's Cup comeback as New Zealand take 4-0 lead

BARCELONA :New Zealand stretched their lead to 4-0 in their America's Cup defence on Monday, leaving challengers Britain to work on ways to win the next showdown after losing out to the holders in a tacking duel and a series of downwind crosses.

The New Zealanders ultimately managed to get slightly more performance out of their AC75 monohull "Taihoro", piling the pressure on British skipper Ben Ainslie during the closest race so far in the first-to-seven-wins series against "Britannia".

Ainslie's team, still smarting from an umpire's decision that went against them in one of the pre-starts on Sunday, again protested against the New Zealand team 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.

The British sailor was part of a U.S.-led team that made one of the biggest ever sporting comebacks against New Zealand to win the America's Cup in San Francisco in 2013.

Ainslie said that a reserve day on Tuesday would give the crew a good opportunity to work on ways to narrow the slight performance gap they were seeing against New Zealand.

Dylan Fletcher, Ainslie's co-helm, said the team still disagreed with Sunday's decision of the umpires and felt a lot of calls had gone against them in their pursuit of the America's Cup, which Britain has not won in its 173-year history.

"The Kiwis chose to engage with us," Fletcher said of Sunday's near-miss, adding that the decision was frustrating and he felt the British had done everything they could.

"I think where we have left it is that we've agreed to disagree," America's Cup chief umpire Richard Slater said