And just as it had been in Rio de Janeiro, so it proved, the 26-year-old cementing his status as the greatest breaststroke swimmer of his generation – probably of all time – in another race against the clock.
This was as guaranteed a gold as there could be in Tokyo, certainly for Team GB and possibly across all countries and sports.
For those few lucky enough to be watching in person at the Tokyo Aquatics Centre and those committed enough to stay up after 3am in the UK, the only race was against the clock.
And Arno Kamminga, the second quickest man of all time, kept him honest although his rival got the win more than half a second clear. Nicole Martinenghi took the bronze for Italy.
And as it transpired, Peaty’s own world record of 56.88seconds set in pre-Covid times at the 2019 World Championship remains intact, his time a full half a second slower.
When Peaty picked up the British team’s first gold five years ago, the medals flowed in quick succession. The expectation is Team GB’s treasure chest will not be quite so laden when they return home in two weeks but it now has that all-important first gold.
On the blocks, the race was already won, the rest of the seven men in the final, some of them the quickest of all time for the 100metre breaststroke, left to scrap it out for the mere morsels of a silver.
The Briton was very briefly behind off the blocks, as is often the case, but, once his turned-out feet and hyperextending knees began to do their thing under the surface of the water, he was quickly clear, his rivals floundering in his wash.
The one gripe of Peaty the showman was that, in both his heat and semi-final, it did not feel like an Olympics with the lack of crowds and relative quiet in the stands.
There was a validity to his argument, although the Team GB contingent who made it to the Tokyo Aquatics Centre did their best to make their voices heard.
He has already said he plans to race in Paris in three years’ time and go onto Los Angeles four years hence. On the current evidence – unbeaten in seven years, it’s hard to see a time when he will beaten in the intervening years.
For the other Briton in the race, James Wilby, who trains in the same Loughborough pool as Peaty and whose nurse mother has been dishing out Covid-19 vaccines the people of York, it was a fifth-place finish.