By Mayuko Ono
TOKYO (Reuters) - Floyd Mayweather has won world titles in five different weight classes and is 50-0 in an unparalleled boxing career but the American could be set for a stunning detour into the world of mixed martial arts after signing with Japanese promoters RIZIN Fighting Federation.gi
And the undefeated 41-year-old, who last year said his boxing career was over after beating Irish MMA fighter Conor McGregor, has told Reuters he could handle himself in whatever format was agreed for the fight on New Year's Eve in Saitama.
His opponent is set to be 20-year-old Japanese kickboxer Tenshin Nasukawa.
Mayweather has never fought professionally under MMA rules and did not specify what format the fight would follow. He said negotiations were ongoing with Nasukawa's representatives and that his skill-set did not end at boxing.
"I can wrestle, I can wrestle little bit. I can box a lot a bit," Mayweather told Reuters in an interview Tokyo on Saturday.
"We will just see. I can do it all. I can do anything if I set my mind to it."
Nasukawa is contracted to RIZIN and competes in their championships in both MMA and pure kickboxing. He has won all four of his MMA fights.
While boxing rules restrict bouts to the use of fists, MMA rules can incorporate kicks, knees and elbow strikes, as well as wrestling, joint locks and chokes.
Mayweather was confident they would reach an agreement that would suit both fighters.
"I am pretty sure that when I speak with the guys from my team we are going to get on the same page so we can go out there and do what we have to do," he added.
Mayweather's fight against McGregor pushed his career earnings to $1 billion (769 million pounds), joining American basketball great Michael Jordan and golfer Tiger Woods as the only athletes to have reached 10-figures in earnings, according to Forbes.
Mayweather had said in September that he was coming out of retirement for another fight with Manny Pacquiao after the two of them had been pictured talking at a music festival in Japan.
His decision to sign a deal with RIZIN was all about timing, he said.
"Everything is about timing, everything takes time and everything is about timing," he added.
"Its also all about entertainment. I love to entertain, I like for people to be entertained and who doesn't want to be entertained.
"It is good to come over to another part of the world, have fun and enjoy each other."
Mayweather expects a good fight against Nasukawa, who won his last kickboxing bout against compatriot Kyoji Horiguchi at RIZIN.13 in September.
"He is very fast, very young and I am pretty sure he wants to go out and entertain his people," said Mayweather.
"I am pretty sure the crowd is going to be on his side but I am there for a great cause. It is a special bout.
"Just for me to be in the ring with a young guy that is hungry ... It is going to be good, very, very good and I can’t wait."
(Reporting by Mayuko Ono and Kwiyeon Ha; writing by Jack Tarrant; editing by Peter Rutherford)