Andy Lee is a former world champion who once lost a fight to a bareknuckle boss.
The fight between Lee and Jimmy Sweeney went ahead in an amateur ring years ago.
Lee went onto box in the Olympics and turned pro with Emanuel Steward in the States.
He is now managing and training Paddy Donovan, who looks to make it four wins out of four at the BT Sport studios on Saturday night. Sweeney took a different route.
“I got bored with amateur boxing,” he said, “and there isn’t a lot of professional boxing in Ireland.
“I drifted away from the gym for a while – until my ex-girlfriend said to me: ‘You’re fat, I don’t fancy you anymore.’
“I decided I had better get back down the gym – and then the chance to box bareknuckle came along.”
As a Traveller, Sweeney describes bareknuckle boxing as “our sport” and has been a star of its rise into a legal sport that millions around the world watch.
The 36 year old from Sligo has won world titles at three weights with what commentators have called “a snake charmer’s style.”
Sweeney waves his hands around in front of opponents, tempting them to make the first move – and when they do, he pounces.
“I have come up with my own style,” he said. “I don’t just get in there and swing.
“I was always an aggressive counter puncher when I was an amateur, but I’ve had to make changes.
“I wouldn’t get away with lots of feints in the amateurs and in bareknuckle boxing, you can’t afford to make any mistakes.
“One punch can change a fight. You can get cut or knocked out. The name of the game is hitting and not getting hit. I don’t take a lot of punishment.”
Sweeney knows that in bareknuckle boxing, you have to be careful where you hit as well.
“I won’t punch above the eyes,” he said. “Anything above that is skull and if you hit that, your hands will go. I try to get the body shots in early and get them to crumble.”
Until he ran into Ricardo Franco last November, the worst injury Sweeney had suffered was injury to his own hands.
He was ruled out of the Franco fight through cuts in the sixth or seven rounds having earlier scored two knockdowns.
They meet in a highly-anticipated rematch at the Indigo at O2 Arena on Sunday, September 6 when Sweeney looks to preserve a proud record.
The only other loss he suffered in his 26-fight career, against Julian Lane, was avenged and he said: “Nobody has ever beaten me twice in bareknuckle boxing – and nobody ever will.”