Longtime boxing coach Freddie Roach has said that he is not too convinced about Conor McGregor's ability as a fighter.
In what is arguably the biggest fight of all time, many in the combat world believe the bout will be an easy win for Mayweather.
Others believe that if the roles were reversed and Mayweather took on McGregor in the octagon, the opposite would occur with the 28-year-old being one of the best pound-for-pound fighters in the UFC.
However, the legendary Roach does not think much of McGregor's fighting ability in general, even if he admits that the lightweight champion is fun to watch.
"He's fun to watch, he's a character, he's – but again, he's not that good of a fighter," Roach told Fight Hub TV.
"He'll let his hands go and so forth, he's a little wild, but as far as boxing wise – I mean, supposedly he went to Wildcard West and boxed with Chris Van Heerden. Van Heerden told me, he says [chuckles] 'I killed him.'
"I mean, I wasn't there so I don't know. Chris Van Heerden is a tough kid and a good boxer, but I just don't think he's [McGregor] in that class of boxing – he's putting himself at a very very high level. I think he's more of a four round fighter at this point."
The 57-year-old is also not fully confident that there are any top level boxers out there that the Irishman could beat, joking that there might be some "stiffs" who are beatable.
"Yeah, I'm sure there's some stiffs out there," Roach joked. "I mean, we've dug 'em up before. Nobody of note though."