Each pair in this elimination round were slated to race a best-of-three series but flat calm conditions on the Waitemata Harbour forced a change of plans to sudden-death single races for both pairs.
Principal Race Officer Peter Reggio told the competitors in the morning that he'd institute a single-race policy if he couldn't start racing by midday. A southerly breeze began to fill in soon after noon and the first race started at 13:40.
The semi-finals on Friday will see Emirates Team New Zealand, top of the table at the end of the Round Robin, face Azzurra after ETNZ skipper Dean Barker (NZL) selected the Italian team as his opponent. That leaves Mascalzone Latino Audi Team against Artemis. The winner of each 'first to two points' series will advance to the final.
Barker said it was always tough choosing an opponent, but he went with Azzurra, the team who triumphed over the Kiwis in the final of the last Louis Vuitton Trophy event in Nice.
"We know the guys well and maybe we will get a little bit of revenge hopefully for Nice. We always have good races against those guys," he said.
Azzurra skipper Francesco Bruni (ITA) said he was confident going up against the home team, who may have a perceived advantage in stronger breezes and their own boats - especially after Azzurra's victory over All4One today.
"I think we sailed the boat very well today in difficult conditions. It was a very, very nice performance from the whole team. I think we are getting better in strong winds. We learn day by day; there is no secret that we would prefer lighter conditions for a match with Team New Zealand. But we are also happy to have a chance to race against them in their conditions and in their boats - we have nothing to lose."
The Swedish Artemis team is rounding into form at the right time and enters the semi-finals with confidence.
"We have won four in a row, and had two fantastic races with the British, which were pretty epic battles in the list of America's Cup races I've been in. I think it's good training for us in preparation going into the rest of the series."
For his part, Mascalzone Latino Audi Team strategist Cameron Dunn (NZL) is sure it will be a difficult match. "We feel we are improving with every race - we started slowly, but we've been chipping away and getting better as a team. We had a very good race with Artemis in the round robins, so we know we're in for a tough battle."
Racing is scheduled to start with a warning signal at 10:00 on Friday morning. The forecast is for fresh conditions.
Thursday's race summaries:
Race One: Artemis def. TEAMORIGIN, 00:38 - Britain's Ben Ainslie seized the start of this sudden death match with flair and defended his lead through the first half of the race and multiple protests only to hand the lead to Paul Cayard's (USA) Artemis on the second weather leg. The Swedish boat made the most of its advantaged starboard entry and pushed TEAMORIGIN below the port layline before the start. Terry Hutchinson (USA), steering Artemis, reported massive shifts in the 16-knot southerly and Ainslie would ride a big leftie into the lead. Pushed outside the left side of the line in the remaining pre-start seconds, he tacked onto port on a big shift and skinned across the bow of the starboard tack Swedish boat right after the gun. The umpires green-flagged the encounter but Hutchinson saw it differently. "Our bowman was saying, "We're going to hit him! But that's the game."
A minute later TEAMORIGIN led by a boat length. Ainslie came back on starboard with a small lead and tacked inches to leeward of the approaching Artemis, who again appealed to the umpires, but to no avail. A big shift on the left kept Artemis in the game and she was only one and half boatlengths behind at the top mark, and trailing by only seven seconds through the leeward gate. It was Ainslie's race until several tacks into the leg he let Hutchinson get to the right in the oscillating shifts, with 400 metres separation. When they converged again, Artemis led by 46 metres. Artemis extended on the run with a damaged spinnaker and the foot tape reinforcing fluttering in the breeze. "What a brilliant job from all our crew, getting back into the race," said Hutchinson. "In hindsight, we didn't do it right up the second beat," conceded Mike Sanderson, who handles the runners on board. "But you know, we need to make sure we don't kill the tiger as well. We have amazing talent at looking up the course and picking up shifts, and if we kill the tiger, we are going to be an ordinary talent."
Race Two: Azzurra def All4One, 00:20 - It was all but over before the start as the German and French boat steered by Sébastien Col (FRA) was trapped by Azzurra skipper Francesco Bruni (ITA) and penalized for failing to keep clear. As the boats turned up for the line, Azzurra was able to hook in to leeward of All4One and Bruni luffed his opponent, drawing the foul, with his aggressive tactics. "I have been criticised during the round robin by my team for being too safe," he said afterwards. "Today I changed a little bit, but the optimum is probably in-between."
Azzura went on to lead across the line clear ahead and luffed up momentarily to gain weather gauge. Still bow ahead and to weather, she took the German and French boat out to the exclusion zone on the left side of the course and maintained her lead through eight short tacks. The margin was nine seconds at the mark. Col overtook to weather on the run but as they both overstood the layline for the leeward gate and went to douse their gennakers, the All4One gennaker went under the boat, spelling the end of her challenge to the Italians. All4One joins TEAMORIGIN on the sidelines.
Full results, video, photos and more at www.louisvuittontrophy.com