Floyd Mayweather has given a surprising response when asked to name the toughest opponent he faced in his career. 

'Money' Mayweather, the self-proclaimed greatest boxer of all-time, is one of the richest, most recognizable athletes on the planet.

A braggart known for his trash talk, but also a boxer famous for his quick fists, he seemed capable of dispatching his rivals - with the exception of Jose Luis Castillo - with remarkable ease. 

His successes in the ring were matched only by an embarrassment of riches outside of it; fast cars, expensive clothes, and flashy watches. Oh, and did we mention a healthy dose of controversy as well? 

Not much has changed between now and then when the undefeated five-division world champion faced eight-division world champion Manny Pacquiao in a fight simply billed as the Battle for Greatness. 

Just over two years later, he would go on to break box office records once again in a crossover fight with UFC superstar "The Notorious" Conor McGregor.

At 44, Mayweather Jr will don the gloves once again when he takes on YouTuber-turned-boxer Logan Paul in an exhibition bout at the Hard Rock Arena in Miami on June 6. 

Of course, 0-1 Paul, the older brother of Jake, likely won't pose much of a threat to one of the greatest to ever do it.

But it's unlikely the shrewd veteran will be leaving much to chance, however, as this will mark the first time he has set foot in a ring since December 2018.

However, Mayweather did start to slow down just a tad towards the end of his career, preferring to pick off his opponents from range rather than risk being caught by a stray punch, with many observers feeling the Fight of the Century failed to live up to expectations.

To his credit, the boxing icon claims "Pac-Man" Pacquiao is the toughest opponent he has ever fought in a storied 25-year career in the ring.

"The best fighter I ever fought probably was Manny Pacquiao," Mayweather said to the ‘Million Dollaz Worth Of Game’ podcast. "It’s because of his movement.

"He’s a hell of a fighter and I can see why he won so many fights and I can see why he’s going down as a Hall of Famer.

"It’s just certain moves he makes."

During the interview, 'Money' May went on to say that the roughest fighter he faced in his career was former IBA light welterweight champion Emmanuel Augustus and recalled that former four-weight world champion Miguel Cotto was also a tough nut to crack. 

"The roughest fighter probably was a guy named Emmanuel Augustus. The ‘Drunken Master’ was tough," he added.

"He was just tough. Miguel Cotto was very, very physically strong."

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