Great Britain's Land Rover BAR were dealt a severe blow in their bid to reach the America's Cup after a failure in their wing handed Team New Zealand the initiative in Bermuda.

Sir Ben Ainslie's Hampshire-based syndicate suffered damage to the wing in the opening race as they rounded the leeward gate, forcing them to retire from the opening race of the challenger semi-finals.

They were unable to complete the repairs to their boat in the available time and they forfeited the second race as a result to hand the Kiwis - who chose to take on the British crew - a 2-0 lead in the first-to-five races play-offs.

Another two races take place today and Ainslie is upbeat his team can bounce back, despite admitting his frustrations at their misfortune yesterday.

He said: "It doesn't get any worse for the team, we felt like we'd made some great improvements overnight, the speed was really good, really positive.

"It's just such a shame for the whole team to have lost two key races that way.

"The positive was we felt like we'd improved the speed and the performance of the boat so we'll come back fighting, it's another day, the team still very much believe we're in this and can make it happen.

"When your back's to the wall that's when you've really got to dig deep and we've got the team to do that.

"We've all been in tough spots before and we've got the experience to know we can come through that.

"It's not going to be easy, for sure, but we'll keep going until the end."

The first crew in each of the two semi-finals to win five races progresses to the challenger final and whoever wins that takes on defending champions Team USA for the America's Cup itself.