"Anything can happen in the sport of boxing."
Of course, Mayweather had to get in a subtle dig, calling McGregor "the second biggest name in MMA," but other than that he was uncharacteristically humble and even outlined a few reasons why he could lose a boxing match to McGregor- if it ever happens.
For one, Mayweather is now 40 and has been retired since 2015. Secondly, McGregor is a "heavy hitter" who defeats fighters standing up, which translates from the octagon to the boxing ring. Lastly, anything can happen in the sport of boxing.
"So, I'm not gonna sit right here and knock Conor McGregor. He's gone out there and done what he's had to do. It's obvious he's done something right thus far to get to the point where he's at."
"I've been off for a couple years and I'm 40 years old now. So, I'm a lot older and he's still in his 20s and I'm in my 40s now. So that could play a major key, we don't know. And he's a heavy hitter."
"Every time he goes out there and defeats fighters, he's standing up. He's in a boxing position and he's beating fighters."
"Does he have a good chance of upsetting Floyd Mayweather? I can't say, but anything can happen in the sport of boxing."
Check out the full video clip below. Mayweather gets into the McGregor talk at about the 3:00 mark.