INEOS Britannia and Luna Rossa Prada Pirelli, the outstanding finalists in the Louis Vuitton Cup were kept on standby prior to racing today as a solid Mediterranean ‘Garbi’ breeze pushed frustratingly above the stipulated 21-knot upper wind-range.

Eventually the breeze settled, allowing the two teams to serve up one of the classic gladiatorial contests that are synonymous with the America’s Cup through its history.

The story ahead of that late afternoon thriller of a second race was around batten issues on Luna Rossa’s mainsail where a number of breaks had pierced the carbon fibre material of the port skin. The only call the Italians could make was to drop and replace the mainsail and they brought their Chase Boat team in to facilitate the change. Unfortunately for the Italians this was right at the time that the Race Committee’s wind sampling dipped below 21 knots, and the opening race of the day was called as ‘live.’

INEOS Britannia duly set up for their start whilst Luna Rossa sat bare-poled on the far-right hand side of the course. As the British entered the starting box, Chief Umpire Richard Slater, disqualified the Italians for receiving outside assistance and awarded the race win to Sir Ben Ainslie’s team.

Further drama ensued an hour later, when, with the wind continually tripping over the wind-limit for the day’s second race, technicians boarded ‘Britannia’ to look at a batten issue low down on their J5 jib. Eventually the call was made to partially drop the sail to remedy the issue.

With the series now 2-1 to the British team, fireworks were expected from the Italians in the next race – the fourth of this first-to-seven-points series – and a slow entry into the starting box from the port end by Luna Rossa was the beginning of a high-pressure race that challenged the sailors to the limit.

INEOS Britannia entered on time from the starboard end at close to 48 knots and immediately set about hunting down Luna Rossa, forcing the Italians to take avoiding action out on the left side, before a long trail back across the starting box with the British close behind on their leeward hip.

With time ticking down, Luna Rossa went for a bear-away and gybe across the British bow, a classic match-racing move, which INEOS Britannia tried to block and were quick to protest. This – the first of several protests from the British during the race – was quickly dismissed by the Umpires.

Off the start line, Luna Rossa held the very slightest of advantages – but it was enough to establish a lead that they never lost over the eight-leg race.

The first two laps saw constant nip and tuck skirmishing between these two very equally matched boats, with INEOS Britannia always the aggressor, positioning their AC75 in awkward leeward positions upwind and appealing unsuccessfully to the Umpires on several occasions as they fought to deliver the ‘get-behind’’ penalty that would have elicited an immediate 75-metre gain. The advanced telemetry in use at this Louis Vuitton 37th America’s Cup means Umpire decisions are based on highly accurate and indisputable data – although this did little to lessen the audible frustration of the British afterguard.

Despite Luna Rossa building what looked like a comfortable lead by the end of the fifth leg, the British refused to accept defeat and continued to chip away at the Italian lead. At the final windward gate they had clawed their way back to within six seconds as the two crews began the last downwind leg. Now within striking distance, the British went full on the attack, but Luna Rossa covered smartly and intelligently to maintain their lead and crossed the line at nearly 50 knots, just four seconds ahead of the chasing British, to level the Louis Vuitton Cup Final series at two races apiece.

Jimmy Spithill, starboard helmsman for Luna Rossa Prada Pirelli, was clearly proud of his team and how they executed the day, saying: “Probably the most frustrating part of the day was just the wind limit, but we did get the race off and from there the boys just bounced back brilliantly, especially after that unfortunate issue with the mainsail.

"It was an awesome race, just a full-on street fight and we love that sort of stuff, it was a lot of fun. It's just great for the team to be under that sort of pressure that sort of stress and load, because you need to be able to go through that as a team. Once again, the guys just didn't falter, just kept their heads up and executed, but also full credit to INEOS Britannia. They just kept coming, but ultimately that's a good one for the team to take away.”

Asked whether he had any concerns about boat preparation after the batten issue today, Spithill added: “No, I think when you're at this end of this technology and really pushing things to the limit, no one's immune from having to face a few curve balls, and in every America's Cup that happens. You're going to face a few things, but again, the team went into action, we got the M1 (mainsail) back up and were able to get racing. It was a good response by the team, and we were absolutely red-lining it today.”

For Sir Ben Ainslie, despite finishing the day all-even again, questions remained in his mind about the umpire calls on the racecourse, and in particular in the pre-start. However he was somewhat tongue in cheek when asked about it, saying: “It was a cracking race, we've had some good ones against Luna Rossa over the years, but clearly frustrated with the pre-start call which we thought was a penalty – but one thing you know about yacht racing is that the Umpires are always right!”

Asked about the further two protest calls that were denied as INEOS Britannia challenged the ‘keep clear’ rule, Ainslie added: “I don't know. I haven't seen the Umpire’s App, and the App really can often tell a different story – and that's obviously what the Umpires are going off. The pre-start one I thought was very, very, close and in our view, it was a penalty. The other two I need to look at because it's just the nuances of whether you get an overlap or not and I’m sure it was very tight.”

Asked about the top-end conditions the team encountered Ainslie revealed: “We were up there again today, and I think we got our top speed of the yacht in one of our practice bear-aways. The sea-state was slightly smaller, which made it a little bit more forgiving for the guys.”

For America’s Cup fans here in Barcelona – who packed the Race Village and FanZones – and for those watching on TV and online all around the world, today’s second race was, without doubt, well worth the earlier waiting around for the wind to settle. High quality match-racing at 50 knots is an irresistibly dynamic and compelling spectacle and this race will live long in spectators’ memories.

With four races completed the Louis Vuitton Cup Final remains on a knife-edge and there is so little to choose between these two teams that it looks like this series could go all the way to the wire. Who will blink first is anyone’s guess, but for certain, whichever team wins will come out of it supremely battle-hardened when they take on Emirates Team New Zealand in the Louis Vuitton 37th America’s Cup Match.

Racing continues tomorrow, Monday September 30, with two more races scheduled in conditions expected to be similar to today's.