Back home in Britain, he's known as Sir Ben Ainslie.
Out on San Francisco Bay, he's the tactician for America's Cup defender Oracle Team USA.
And really, Ainslie can't lose even if Oracle fails to defend the America's Cup.
Signed to steer the B boat to help get skipper Jimmy Spithill into fighting trim, Ainslie never expected to sail in the match against Emirates Team New Zealand.
His ultimate goal was to gain the experience needed to help lead a British campaign for the next America's Cup, which is looking more and more like it'll be held in Auckland.
After the American powerhouse stumbled badly in losing four of the first five races, Ainslie replaced American John Kostecki as tactician. There's been a noticeable uptick in the crew's performance and Oracle is sailing much better upwind after modifying its 72-foot catamaran.
Still, Team New Zealand leads 7-1 and needs two more victories to wrest sailing's biggest prize from Oracle.
Monday was an off day, with Races 11 and 12 scheduled for Tuesday, weather permitting. Docked two points in a cheating scandal, Oracle needs eight wins to keep the oldest trophy in international sports.
As this America's Cup approaches a conclusion, Ainslie has to keep an eye on the next one. New teams need to be put together quickly and serious amounts of cash need to be raised.
While Britannia once ruled the waves, it has failed miserably over the last 162 years to win back the Auld Mug.
"It's a huge part of our maritime history that, well, is missing from our maritime history," said Ainslie, the most successful sailor in Olympic history. "It started in 1851, around the Isle of Wight, and we've never seen it since."
Ainslie would seem to be the perfect sailor to bring the silver trophy back to British shores. He was knighted by Princess Anne in March, seven months after winning his fourth straight Olympic gold medal. He also has a silver medal from 1996.
Ainslie had been part of the most recent British syndicate, Team Origin, which abandoned plans for the 34th America's Cup after the 72-foot catamarans were introduced. Funding also was a consideration.
Britain hasn't had a team in the challenger series since the 2003 America's Cup.
The last time Britain was in the America's Cup match, in 1964, the Beatles were making far bigger waves than sailors from Old Blighty.
In the decades since, two of Britain's former colonies, Australia and New Zealand, have won the America's Cup. The Kiwis are closing in on winning it again.
Maybe the British did their best sailing back in the days when cannons stuck out of the sides of their seagoing vessels?
After all, in the buildup to the London Olympics, Ainslie was called Britain's greatest sailor since Admiral Lord Nelson, who was killed while leading his fleet to victory over the French and Spanish fleets at the Battle of Trafalgar. A statue of Nelson rises high above London's Trafalgar Square.
"I think it's just really been the fact that we haven't been able to get all the critical elements together, the people, the funding, at the right time," said Ainslie, 36, who felt the comparison with Nelson was hype.
The Kiwis are expected to re-establish a nationality rule if they win the Cup. There is no such rule currently, although 13 of the 15 sailors on Team New Zealand's roster are Kiwis, with the other two being Australian.
Since Kostecki was replaced by Ainslie, there's been only one American sailing on Oracle's 11-man crew.
Are there enough good British sailors to crew an America's Cup campaign?
"Undoubtedly. We've got some fantastic sailors," said Ainslie, who pointed out that British sailors were with eliminated challengers Artemis Racing of Sweden and Italy's Luna Ross. "We've definitely got the talent."
Ainslie knows it would be tough to mount an America's Cup campaign in faraway New Zealand, and that it would probably rely more on private money than on corporate sponsorships.
"I'm not interested in leading a team that doesn't realistically have a good chance of winning," he said.
Ainslie envisions himself in a role like Spithill's, skippering the boat and leading the sailing team. He hopes Grant Simmer, general manager of Oracle Team USA, would run the campaign. Simmer has three America's Cup victories, including serving as navigator with Australia II, which in 1983 ended the New York Yacht Club's 132-year winning streak in the America's Cup.
Ainslie's addition to Oracle's crew has changed its complexion.
"It just gets really, really noisy with all the gold clanging around in the back," joked Spithill, referring to Ainslie's four gold medals and strategist Tom Slingsby's gold medal from the London Olympics.
"Look, we've got a lot of depth on our team, with John, Tommy Slingsby and obviously Benny," Spithill said. "We're pretty fortunate that we've got these guys. It's something we had to set out to do, was to build two strong in-house teams to push each other."
As for knighthood, Ainslie said it's "a huge honor as a proud Brit," but that it "seems to be much more of a fascination here in the states than it is back home. Back home, nothing really changes."