The UFC heavyweight champion has welcomed the possibility of a crossover fight with the WBC and Ring magazine titleholder after his showdown with Ciryl Gane in the main event of UFC 270 this weekend.
Ngannou’s chances of beating the Gypsy King are slim at best, with many boxing fans
And Maccarinelli, who knocked out Roy Jones Jr in Moscow in December 2015, doesn’t think it would be competitive at all.
The former WBO cruiserweight champion told Sky Sports: “This is what we’re talking about, is he switching to boxing as in to start a career or is he switching to boxing to fight one of the top boys?
“If he’s planning to fight one of the top boys he hasn’t got a hope in hell, just like they wouldn’t have a hope in hell in a cage with him.
“It’s two different sports, it’s two different rule sets, two different ways of holding your legs, two different ways of how you approach a fight, it’s just crazy.
“You think, Ngannou coming in talking about Joshua, Fury, Uysk, they’d stand him on his head, Wilder, Joe Joyce.
“It’s a different setting and people would say about his power, but it’s just totally different.”
Maccarinelli, 41, isn’t convinced Ngannou has the stamina to keep up with his fellow Briton, so much so he reckons the MMA KO king would be ‘tired out in a couple of rounds’.
He added: “[Floyd] Mayweather fought [Conor] McGregor, all the McGregor fans are like ‘he’s the hardest puncher he’s ever faced’, it’s just different levels.
“People will say about the gloves, a good friend of mine John Phillips, a UFC fighter, he tried a pair of my gloves on and he said he’d rather get hit with an MMA glove, it’s not got a lot of padding, all the weight is in the wrists.
“What the boxing glove does is it’s got that bigger target, which the MMA glove hasn’t got.
“With Ngannou he’d come out swinging, and he’d still be dangerous, I’m not saying he can’t punch because he obviously can, but he’s going to come out swinging and fight one of these top boys like Fury and they’ll just make him messy, he’d be tired out in a couple of rounds the way he fights, he’d have to change his tactic.”