Team GB’s freestyle relay heroes swam into the record books on Tuesday night with a superb defence of their 4x200m title, then set their sights on an historic "three-peat" in Los Angeles in four years' time.
Leading from gun to tape, Duncan Scott, James Guy, Tom Dean and individual silver medallist Matt Richards became the first Brits to defend an Olympic relay title, as well as the first swimmers from any nation to do so as an unchanged team.
Prior to Team GB's success in Tokyo, American teams featuring the great Michael Phelps had won the event at four Games in a row, but here the US were forced to settle for silver, with Australia taking bronze.
"To be crowned Olympic champions again with the same quartet is pretty special," said Guy, now a six-time relay medallist at the Games. "We will have to do four more years and beat them on their home turf."
At 28, Guy admitted he is no certainty to make it to LA, but team-mate Richards, already a back-to-back champion at 21, is ready to lead the charge.
"It's a privilege and an honour to be a part of that team," he said. "I have seen Jimmy on the golf course, he is not old! He is still going.
"I will be planning on still being there. Who knows about the other boys, but let's go for the three-peat."
Britain had rested individual finalists Scott and Richards for the morning heats and still qualified fastest for the evening's final to confirm their status as heavy favourites.
The Americans, however, stuck within half-a-second at every changeover before a devastating final leg from anchorman Scott finally saw Britain pull clear.
Another gold takes the 27-year-old's career tally to seven medals in all, fewer only than Sir Jason Kenny and Sir Bradley Wiggins among British athletes, and as many as fellow Scot Sir Chris Hoy, though he was quick to nip comparisons in the bud.
"I'm nowhere near the level of athlete Chris Hoy has been, I think that's taking away from what he's achieved," he insisted. "I've had so many medals won by relay teammates, I can't thank them enough for what they've done.
I don't think I should ever be compared to Sir Chris. He's well above what I've achieved
"I don't think I should ever be compared to Sir Chris. He's well above what I've achieved. It's pretty cool in terms of numbers, but he's got quite a few better colours than I do!"
Another trip to the top step of the podium for Guy and Dean moved them level with Adam Peaty as the most successful British Olympic swimmers of all-time on three gold medals.
Remarkably, Guy had broken his nine-year-old personal best with his lead-off leg in the heat and then swam to within five-hundredths of a second of the same mark a mere nine hours later.
Afterwards, the three-time Olympian revealed he came close to quitting the sport last year, before a change of training set-up reinvigorated him in the run up to Paris.
"I felt quite lost last year," he said. "I lost a lot of faith in what I was doing. Having that change of programme, that new environment was very important.
"Everyone sees the highs of the sport without seeing the lows. I've come back crying on the phone to my girlfriend, just not knowing what to do. This year, I'm in the form of my life, so it shows that if you're doing the right stuff and the right work, then you're happy."
