The Dubliner is currently on a break until the birth of his first child and won his last fight after defeating Eddie Alvarez to win the lightweight title at UFC 205 in November 2016. Since then, there has been a talk of a potential fight between McGregor and the American boxer in a boxing ring.
Mayweather defeated Andre Berto in September 2015 to remain undefeated after 49 fights is willing to come out of retirement to face the Irishman. Hardy, who has recovered from Wolff-Parkinson-White syndrome and has got the medical clearance to enter the octagon, believes McGregor will struggle to beat the 40-year-old in a boxing match.
Hardy also went on to explain why a fight between McGregor and Mayweather will not be entertaining for the fans.
"If it actually happened, I don't think it would be nearly as exciting as people think it would be," Hardy told Newsweek.
"It's superstars. If you had Jennifer Lopez fighting Kim Kardashian, people would watch it. It doesn't really make a difference whether it's a boxer against a mixed martial artist, in my opinion it's not about that.
"In my opinion it's about Floyd Mayweather and Conor McGregor. It just so happens that they are both combat sports athletes."
"I struggle to believe it's ever going to happen, if I'm honest. Obviously if it happens, I would love to watch it and I would be fascinated in the outcome.
"I think in a boxing ring McGregor is going to struggle to put a hand on Mayweather, purely because as I was saying earlier, we know the technology of boxing and Mayweather has mastered it.
"And boxing doesn't transfer over to mixed martial arts exactly. There are a lot of changes you need to make to your stance, to your movement, to the way that you throw punches. And McGregor is a great fighter, Mayweather is a great boxer."