At 31 and a new dad, Phelps says he wants to enjoy fatherhood. He would know also that he was the second oldest swimmer ever to win an individual gold medal in these Games and he has not set a world record since 2009. He is smart and I think he means what he says.

He once said that he wanted to change the face of swimming. He has done that. You see it when you see the photos of him with a young Katie Ledecky or Joseph Schooling. He will be a role model for generations of swimmers to come.

However, I hope he takes that further.

I believe Michael Phelps could have a huge role in helping to clean-up doping in sport – not just swimming. He has unassailable moral authority to do so. If the GOAT spoke out about doping, even the International Olympic Committee would have to listen – despite their brass monkey approach to most issues.

The previous GOAT in the swimming pool, the legendary Mark Spitz, said in Bob Schaller’s 2008 biography of Phelps, that Phelps is not only “the greatest swimmer of all time and the greatest Olympian of all time, he’s maybe the greatest athlete of all time.”

Eight years on, I reckon there’s no maybe about it.

By Jaimie Fuller