While there has been no official confirmation, it is becoming increasingly likely Team New Zealand will have just two rivals in next year's Louis Vuitton Challenger series.
Swedish team Artemis and Italy's Luna Rossa will do battle with Team New Zealand for the chance to challenge Oracle in the America's Cup finals in September 2013.
The fourth challenger signed up, Team Korea, has yet to start building an AC72 catamaran and it is unlikely they will pull together the estimated $100 million needed to mount a credible challenge.
This week's World Series regatta in San Francisco will be the last time we see the challengers race at the America's Cup venue before they return next year in search of the big prize.
Oracle have already taken the opportunity to show the challengers what they will be up against in the America's Cup final. While the other teams were out on the water preparing for the second round of the world series in their scaled-down AC45s, the Cup defender decided to take their newly-repaired AC72 out for a spin on San Francisco Bay.
On the far shore, at Alameda, lies the Artemis headquarters in which sits their bright-red Juan Kouyoumdjian-designed (or Juan K if you're intimidated by long surnames) AC72. Artemis haven't got as far as putting their catamaran in the water yet - the boat is missing it's triple element rig after it failed while being tested in a 18m trimaran in Valencia. But Artemis skipper Terry Hutchinson said they are hopeful of "getting the thing wet" in the next few of weeks.
"I think we have to be smart about when we put our boat in the water. We can't feel the pressure from the other teams to just rush out there on the water and not to the job properly," said Hutchinson. "It's too big a project to make any mistakes."
The benefit of the delay in their launch means Artemis have had a good look at what Oracle and Team New Zealand have come up with in their designs.
Both teams have demonstrated an ability to foil, but it remains to be seen whether it will be viable while racing the tight course in San Francisco Bay.
Hutchinson said his team would certainly look at foiling as an option, but they were aware of the risks and rewards.
"You would be naive not to look at it and think hard about it. What you have to look at in the bigger picture is what goes around the race course the fastest.
"The trick will be whether you have the space or the room to allow the foiling to work for you."
While their AC72 remains onshore, there has been movement for the Artemis crew.
Australian Nathan Outteridge has made the switch to Artemis from Team Korea - handing 21-year-old New Zealand sailor Peter Burling his opportunity with the Korean team. Outteridge, who won gold ahead of Burling in the 49er class at the London Olympics, will helm the Swedish outfit's second boat - Artemis Red.
Outteridge said he made the move because he wanted to be part of a team that had an AC72 programme in place.
"This is a really good chance for me to join a professional team and see how it works for next year into the Cup. It was kind of an offer I couldn't refuse. As much as I wanted to stay with Team Korea, it didn't balance out as nicely," said Outteridge. The presence of the young Australian will put the heat on Hutchinson for the top job next year.
Like Artemis, Luna Rossa also have two boats competing in the world series, the first helmed by Britain's Chris Draper, the second by veteran Spanish sailor Iker Martinez, who skippered Team Telefonica in the 2011-12 Volvo Ocean Race.
Martinez is also making his World Series debut in San Francisco, with Volvo and Olympic commitments preventing him from joining the team until now.
His experienced will be a huge boost to the Italians.
The benefit of running two boats is it keeps the sailing team competing to keep their spots. But for now, Martinez said his focus was on learning to sail multihulls.
"I've only sailed [the AC45s] one week, but it looks like a good platform. I'm excited to keep going and go to the big ones. I've never sailed catamarans before, maybe a Hobie 18 once on vacation, so that's the biggest step," he said.
An evolution from the successful Prada campaign of the 2000 America's Cup, Patrizio Bertelli's Luna Rossa entered into a ground-breaking partnership with Team New Zealand late last year to ensure they could make the startline in 2013.
The Italians bought the design of Team New Zealand's first boat and, at the end of the testing period, both teams will go away and build their second AC72 independently.
While the Kiwi syndicate launched NZL01 in July, Luna Rossa won't have their boat in the water until later this month.
They plan to launch the boat in Auckland on October 26 and will do all their testing in New Zealand, although there are strict rules around information and data sharing between the two teams under the America's Cup protocol.
Knowing what their own boat is capable of, and the experience in the Italian team, Team New Zealand will see Luna Rossa as their strongest competition for the Louis Vuitton Cup.By Dana Johannsen Email Dana