They helped bring the America's Cup back to New Zealand and remain teammates but for a couple of weeks this month Glenn Ashby, Peter Burling and Blair Tuke will be rivals.
The trio will be among more than 100 sailors who will be lining up for the A-Class world championships at Hervey Bay north of Brisbane and all three will have designs on winning the title.
Ashby is the king of A-Class sailing, having won nine world titles dating back to 1996, and three times been runner-up. One of his wins was off Takapuna in 2014 when Tuke finished second and Burling was third.
All three have been training together at Ashby's Australian home in Port Phillip Bay and are among the favourites when both the Australian national championships (Nov 11-15) and world championships (Nov 16-23) get underway.
"I'm just remembering how to sail these things," Tuke said on an Emirates Team New Zealand Facebook post. "They have got quite a lot faster than the last time [I sailed them] four years ago.
"The foils are a little more stable and the rudder has a little more lift compared to before so it should be easier to foil upwind now, which will be good."
It's part of the reason why the A-Class catamaran has been described as the ultimate single-handed dinghy. They weigh only 75kg, fully rigged, and can travel in the vicinity of 20 knots upwind and the fact they often lead other classes in terms of design development has given Emirates Team New Zealand a platform to experiment.
"The quest for speed never really finishes," Ashby said on Facebook. "We have been testing the sails, mast settings, foils and a lot of setups. It has been great. It has a lot of relevance for high performance boats into the future."
Someone who will get a first-hand view of the battle between the trio and the other top A-Class sailors, and who wants to be at the pointy end of the fleet as well, is Micah Wilkinson.
The 22-year-old is Olympic campaigning in the Nacra 17 but has been sailing a variety of foiling boats recently as his sailing partner, Liv Mackay, recovers from hip surgery.
Wilkinson is a self-confessed speed freak so expects to be in his element in the next couple of weeks.
"It’s overpowered, it’s fast, it’s foiling. It’s exactly the type of boat for me.
"They are really loose foiling upwind. It’s not like a Nacra or Moth, which is quite controlled foiling upwind. You are fully loose and there are some big crashes. As they’ve developed foiling, it’s really exciting.
"They are also hugely demanding. The boats are really physical. Foiling upwind takes a big toll on the body so, over a six-day period, I’m hoping I’m fitter than a bunch of dudes around here."
Wilkinson won't know how he really stacks up until racing gets underway but he's realistic.
"I have never raced it before so I have no idea," said Wilkinson, who is staying with Tuke and Burling. "The junior title is probably what I’m going for, the under-25 title. I would like to win that or at least podium.
"I have never sailed against Pete and Blair competitively so it’s a chance to have a crack against them and learn from them. They are the benchmark and where I want to be in 5-10 years."
For the first time, two fleets will be run at the world championships - foiling and classics - and both will feature former world, Olympic and European champions.
Defending champion and three-time winner Stevie Brewin will be looking to upstage Ashby, as will New Zealand champion Dave Shaw, who finished fourth last year, and Volvo Ocean Race winner and recently-crowned women's world sailor of the year Carolijn Brouwer is one of three females in the fleet.
But it might not be all about twitchy catamarans and a star-studded field, with migrating humpback whales likely to add another dimension to racing.