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Join us at 3pm Saturday, when the spotlight goes on Dean Barker and American Magic, when they face Team UK again and Luna Rossa for the first time, hoping to chalk up some points on day two.
Prada Cup, Round 1, Race 2
INEOS TEAM UK V LUNA ROSSA PRADA PIRELLI
Team UK win by 28 seconds
Leg 6 - The race is Team UK's to lose and they're not making mistakes. They're 300m up.
UK are up to 43 knots and are covering the Italians down the sprint to the line.
Team UK cross the line ahead - magnificent performance today - 28 seconds clear.
Leg 5 - This contest has tightened right up again to less than 100m, but the Brits have extended away again, heading right upwind. They're just covering their rivals.
Luna Rossa tack right, Team UK follow. Both lay for the mark now.
The Brits tack around the right mark to head down the last leg, Luna Rossa take the left and have cut the margin to just 13 seconds. Any mistake is crucial now.
Leg 4 - Luna Rossa fall off the foils and lose ground at the top mark. That's costly - all the gains they made upwind have been squandered.
The Italians are dragging both foils in the water, which won't help them at all. Team UK are now about 500m ahead downwind.
Team UK tack to the left gate and down the right side of the course for the fifth leg. They fall off the foils momentarily, but are immediately back up.
Luna Rossa are 23 seconds behind at the mark.
Leg 3 - Britannia reaches the boundary and tacks left, with boths boats about 32 knots. The lead is just under 300m.
Luna Rossa seem to be making ground upwind, heading right. The lead is down below 200m.
Team UK seem to have laid for the mark from the centre of the course, but they will tack at the last minute for the right mark.
Luna Rossa round 23 seconds behind.
Leg 2 - Luna Rossa fall off their foils, so they will lose more ground. The Italians pick it up quickly and gather good boat speed, perhaps better than Team UK.
Ainslie has extended the lead to about 300m downwind. He's aiming for the right mark and rounds smoothly, heading right immediately.
Spithill also takes the right mark, 22 seconds behind, but splits left.
Leg 1 - The Brits have tacked back towards the centre of the course and cover the Italians. Both boats are heading left, but Luna Rossa tack right at the boundary.
The lead is 100m, but Team UK have tacked to cover their rivals to the right. There's an old-fashioned tacking duel developing here.
They're fairly even now, but Luna Rossa has gone wide beyond the left layline and tack to the right mark. Team UK is already there and lead by 15 seconds.
Start - Team UK will have first bite at the start box from port side. What will Jimmy Spithill bring to the start from Luna Rossa?
Luna Rossa are well behind Team UK and may be trying to seize the windward position, just as the Brits did in that first race.
Both boats locked together now, but Team UK now have windward again. They're late to the start, but the Brits have snatched the advantage and head down the right side of the course again.
4pm - Next up, the Brits are straight back on the track to face Challengers of Record Luna Rossa. If they can add this scalp to their collection, Sir Ben Ainslie has produced a miracle turnaround.
Prada Cup, Round 1, Race 1
NYYC AMERICAN MAGIC v INEOS TEAM UK
Team UK win by 1m 20s
"It feels a bit better than six losses or whatever it was," admits Ainslie. "We left it a little bit late, but managed to find the pace when it counted... in this breeze.
"The right hand side was stronger - North Head - as we saw in the races a couple of weeks ago.
"That race was for the rest of the team back at the dock - our designers, our engineers, our shore team, our boat builders. They've had an epic 2-3 weeks turning this boat around.
"I just said to the boys, we're a long way from out of the woods yet. That's just one good race, but it's a huge motivator for our team and hopefully we can continue that momentum now."
Leg 6 - Team UK retain their 1m 08s lead around the last mark and are racing towards the finish, when Barker finally rounds.
Remember, the Americans are favoured to win the challenger series, but they've been pantsed today.
Ainslie heads to the finish-line and cross for first blood in the challenger regatta. Who would have picked that?
Barker will be stunned by that result and he's lost ground on the last leg, eventually crossing 1m 20s behind.
Leg 5 - Upwind, Ainslie is sailing away from Barker, who needs a miracle - or disaster for Team UK - to get back in the contest.
UK laying on the righthand line. They head for the left gate, but tack right at the last minute for the favourable wind down the final leg.
Leg 4 - The Brits seem to have more speed downwind, reaching 42 knots. They're about 1km ahead and look unbeatable.
They round the mark to begin the fifth leg and Magic are way off to the left, only just laying for the mark. They're now 1m 08s behind.
Leg 3 - American Magic fall off their foils rounding the mark, so they lose more ground.
Team UK have tacked back toward the centre of the course, but no further, as they turn back to cover the Americans and protect their 300m lead.
Both boats are travelling 33-34 knots upwind. Team UK take a middle track towards the gate and will tack around the right mark.
Magic have zig-zagged rather too much and slipped 47 seconds behind.
Leg 2 - Nice start from Sir Ben Ainslie and he has Britannia humming at 38-40 knots downwind.
Magic initially split to the other side of the course, but now jib back towards their rivals. They're well behind.
This is a completely different UK team to the one we saw before Christmas - they're now 400m ahead as they near the second mark. Their lead has extended to 19 seconds, as they head down the right side of the course and Magic split left.
Leg 1 - Barker has American Magic ahead early, so the British tack away to the right, looking for an edge.
That move actually sees Britannia edging away into the wind.
Team UK arrive at the layline, but tack sharply, which may mean they need another before the gate.
Magic have gone outside the layline, but head straight for the mark. Team UK have had to tack again, but still round first, 11 seconds clear.
Start - Both boats are preparing to enter the start box on Course C. Magic is the first to arrive and enter first from the port side, Team UK to follow.
The Americans have gone way right to approach the line, with Team UK tracking them.
Both cross the line at the same time, but the Brits have best position against the wind.
3:05pm - First up, the Brits will take on the Americans, who have Kiwi Dean Barker at the helm. He will know these waters very well, after growing up on Auckland's North Shore.
The New York Yacht Club held the America's Cup for 132 years, so it has the proudest tradition in this event. American Magic are favourites to progress past the challenger round this time, so this will be a huge obstacle for the Brits.
Kia ora, good afternoon and welcome to Newshub's live coverage of the America's Cup challenger series, sailed on Auckland's Waitematā Harbour and Hauraki Gulf.
Today marks the first day of really meaningful racing, after the three challengers - Luna Rossa Prada Pirelli, INEOS Team UK and NYYC American Magic - along with holders Emirates Team NZ, contested the world series build-up event before Christmas.
Over the next six weeks, only the challengers will face off for the Prada Cup and the right to take on the Kiwis for the 'Auld Mug'.
Weather for Friday will see 10-15 knot winds from the southwest, so racing will take place on Course C, with North Head and Bastion Point providing the best vantage points for landlubbers.
Most eyes today will fall on Team UK, who lagged far behind the other teams in pre-Christmas racing... to the point where they actually failed to finish a couple of their contests.
Skipper Sir Ben Ainslie is a four-time Olympic champion and one of that nation's greatest-ever sailors, so you can bet he's burnt the midnight oil fixing his boat (and perhaps crew) to bring it up to speed.
They face both their challenger rivals in the opening round and two losses would immediately put them on the back foot in their aspirations to lift the trophy.
TAB odds: American Magic $1.75, Luna Rossa $3, Team UK $5
Team UK skipper Sir Ben Ainslie reveals wholesale changes for Prada Cup
INEOS Team UK skipper Sir Ben Ainslie is confident his boat has improved since it was brutally exposed in last month's America’s Cup World Series.
But whether those improvements will see them genuinely contend in the Prada Cup challenger series, which starts Friday, remains to be seen.
The British boat will race NYYC American Magic and Luna Rossa Prada Parelli for the right to challenge Emirates Team NZ for the ‘Auld Mug’ in March.
In their first outing on NZ waters, Team UK were completely outclassed in the warm-up competition, losing all of their races and leaving many questioning the boat's credentials.
A day out from the start of racing, Sir Ben insists his wider team have made wholesale changes to their AC75 since their disastrous debut.
"We have got a new rudder, a new elevator, a new mast, a new mainsail, headsails, aero modifications to the hull and we've changed systems to the hull, so we have been quite busy," says the four-time Olympic gold medallist.
But the team's glaring and well-publicised weakness has been their inability to perform in lighter winds, and the extent of those improvements in that area will be immediately put to the test in a doubleheader against the Americans and Italians on Friday.
"We'd love to race in the stronger breezes, I think that's no secret," Sir Ben admits. "Everyone can see that and our competitors can see that.
"The trick is we can't control the weather, of course. I think we're seeing a medium breeze for Friday, and a bit lighter for Saturday and Sunday.
“We have justifiably taken quite a bit of flak for our performance and it’s been my job to protect my team from that. We have improved a lot from where we were in light airs.
“Have we improved enough? Time will tell."
Team NZ boss Grant Dalton has warned against dismissing Team UK's threat based on their world series races, insisting their skipper's quality will come to the fore when it matters most.
"You just can't write them off - it wouldn't be fair, it wouldn't be right," Dalton has told The Times. "With the talent behind that organisation, you write them off at your peril,"
"The one thing you can never dismiss or ignore is the fact that Ben is the most decorated Olympic yachtsman in history.”
Sir Ben (43) is as eager as his doubters to see the result of his team's hard work on Friday.
"I think we have come a long way down that road of improvement, but there is still more to come, as these other teams are improving every day.
"Pretty much every day they are coming with new upgrades to their boats. We are excited to see how much of a jump we have made.
"I think we can be competitive, certainly in the medium to stronger wind range. The lighter airs, we really still don’t know."