Injury-ravaged James DeGale followed Muhammad Ali into the deep end when Achilles’ tendonitis drove the marathon man off the running track.
The Greatest was snapped submerged in Miami in 1961 after a trainer explained the benefits of subaqua training to a 19-year-old Cassius Clay.
Super-middleweight DeGale, 33, has taken the plunge later in life ahead of his must-win Saturday night fight with Chris Eubank Jr.
But he told SunSport the deep solitude of his Westminster Lodge pool in St Albans has helped him focus on his sink-or-swim showdown against his old rival.
He told SunSport: “Not running has been difficult because that is the first thing you are taught as a boxer, it’s how you measure yourself and your stamina and your mental strength early on.
“I have had to stop and suddenly put all my confidence into other new things like swimming.
“You can run with your pals or listen to music but under that water you are on your own, in the zone with your own thoughts.
"It means you are tackling the work head on, with no distractions, nothing around to make it easy or encourage you to slack off.
“There is a lot on the line in this fight and I really think it should be a retirement fight.”
When DeGale won gold at the 2008 Beijing Olympics he was British boxing’s golden boy, long before Anthony Joshua followed in his footsteps.
But losing a 2011 West London grudge match with George Groves, after some spiteful trash talk, knocked Chunky off course.
Boxing fans recognise the southpaw’s achievements, winning a 2015 world title in America and defending it three times on the road, but some mainstream fans seem to have missed the boat.
He said: “The reason I’m fighting on is firstly for the glory but also to prove the doubters and haters wrong.
“I’ve had a good and long career, with ups and downs, but the main thing is I have achieved everything.
“I am a history man, I have done it all and people cannot take it away from me.
“Since I won my world title, people have taken their hat off and called me a good fighter.
“People recognise I have made history and given me credit, the Groves stuff was just part of my journey.
“People think I am just doing this for a payday. But I am a proud boy, I want the glory for my team, my family and fans.”
Tickets are available from AXS.com and Inner Ringside/VIP Hospitality from sportandmusic.co.uk This fight will be shown exclusively on ITV Box Office. Visit itvboxoffice.com.
