Floyd Mayweather Jr has no intention of prolonging his career, even if victory over Manny Pacquaio moves him a step closer to one of boxing's most legendary records.

The undefeated American defends his 47-0 record against Pacquaio in Las Vegas this weekend and has a fight against an opponent yet to be confirmed slated for September this year.

Success in both would take his undefeated streak to 49 – matching legendary heavyweight Rocky Marciano.

However, Mayweather has little interest in writing his name further into boxing folklore, and claimed the millions of dollars he has made during his career will give him more comfort than any legacy in the ring.

"My father is right, September will be my last fight," Mayweather said. "It's about that time for me to walk away.

"Rocky Marciano was a hell of a fighter, I take my hat off to the guy - Marciano, Ali, Ray Robinson. Right now I'm TBE [The Best Ever] and Saturday before the fight and after the fight I will still be TBE.

"Even if I didn't fight Manny Pacquaio, that doesn't define my career.

When asked specifically if he would look to surpass Marciano's "special" record, Mayweather bullishly responded: "No. No. No it's not [special]. For you it is, not for me."