America's Cup: Winning today was crucial - Glenn Ashby on Team New Zealand's BAR series win

Team New Zealand skipper Glenn Ashby said it was crucial his team wrapped up the challenger semifinals today in order to buy the shore crew more time in the boat shed.

Just 48 hours after their boat returned to their dock a mangled wreck following a near-catastrophic capsize, Emirates Team New Zealand booked their place in the Louis Vuitton challenger final after dispatching Ben Ainslie Racing 5-2.

Their final opponent is still to be determined, with an intriguing battle playing out in the other semifinal between Artemis and Dean Barker's Team Japan. The Swedish team lead the first-to-five series 4-3 after completing a hat-trick of wins today. The deciding races are scheduled for tomorrow's reserve day, with the final to get underway on Sunday.

Ashby said it was a relief for the team to wrap up their series today to give the crew a much-needed day off after a tough week, and ensure they can continue to work on getting their boat back into top shape.

"It's fantastic for the guys to have a bit of a spell tomorrow. We will regroup - there's a lot of debriefing to do with our boat-handling, but we'll go over that in the next couple of days," said Ashby.

"It gives the shore crew a bit of time as well. There's a few bits and pieces that we're changing , so it means they have the opportunity to do that without the same time pressure."

The Team NZ skipper and wing trimmer was disappointed the crew were unable to wrap up the series in two races today. Putting Wednesday's capsize drama behind them, the Kiwis came out and won the opening race, despite an issue with one of their daggerboards in the pre-start.

By the time the issue was resolved, BAR had 26 second advantage over the New Zealand boat - a lead the Kiwis slowly chewed up over the next 5 legs, taking the lead on the final beat.

With a clear speed advantage over the British boat, Team NZ looked on track to make a short day of it, but Ainslie kept the series alive for his team with a brilliant win in the second race of the day.

"The second race to be honest we sailed like a bucket of spanners - we couldn't have made it any worse for ourselves if we tried. So a lot of lessons and good takeaways to debrief about that second race - we'll be spending a lot of time going over that and working through a few things there," said Ashby.

"I feel a wee bit disappointed in the way we got the boat around the track a couple of times. We definitely could have made our life a lot easier there, but to come away with 2 points out of the day that was our goal.

"The BAR guys sailed a much better day than we did today, their boat handling and picking the shifts - particularly in two of the three races - was very good. They were very tough opponents and we were fortunate to make it through with the package that we do have."

Ashby also revealed the cause of the daggerboard issue in the opening race was not related to damage caused in the capsize earlier in the week.

"We had a little bit of water in the leeward cockpit and something fell off and pressed one of the buttons, which actually pulled the daggerboard up at exactly the wrong time in the pre-start. We managed to get that sorted and then we were on our way.

"The win today was really a win for the shore team. They did a stellar job from having the boat in pieces 48 hours ago to actually being back in the water and sheet it on and sail hard today."