Before Floyd Mayweather announced his retirement, he earned his 49th win in the ring with an easy decision over Andre Berto in September 2015.

As the last man to fight the great Floyd Mayweather, recently sat with Berto, who describes — in detail — what it’s like to be in the ring against arguably the greatest defensive boxer of all time.

“He thinks defense first, while all of us think offense first, like ‘We got to get em, get em, get em.’ He’s always thinking defense. He’s always, looking, looking, looking,” he explained. “He’s put you in a place where he’s so defensive and elusive, and you steady punching… you keep swinging and you see him looking at you. He puts you in a place, like ‘Okay, if I keep swinging too much, I’mma hang myself out there to get hit.’ Because, he’s seeing all this (motioning Mayweather’s head movements).”

According to Berto, Mayweather is unlike anyone he’s ever faced, specifically pointing out how aware of everything going on, from the clock to his breathing.

“He’s very good at dictating the pace too. He manages his time,” the boxer explained. “He looks up at the clock like four times during a round. He’ll move around, move around, look at the clock, grab you tight, look at the clock… bop, bop, he’ll hit you two or three times. Just enough to win the round.”

“I’ve never been in there with somebody that’s so observant. Very observant of everything that’s going on.”

Floyd Mayweather recently said that he’s officially coming out of retirement to fight UFC superstar Conor McGregor. Word is, both sides are working out the details for a superfight.