The news is a lot to unpack as Mayweather has been retired seemingly since fighting Andre Berto in September of 2015 with a tune-up novelty fight between himself and Conor McGregor previous year that was a rating success.
Nasukawa is on of Rizin's leading stars, holding a 4-0 MMA record, but being best known as a kickboxer who holds a ideal 27-0 record.
While Nasukawa has had kickboxing rules fights at two of the last four Rizin events, MMA would appear the most likely middle ground for Mayweather to take him on - by no means a gentle introduction to the sport.
Believe it or not this is actually happening, with Mayweather joining Nasukawa at a press conference in Toyko yesterday to confirm the fight, though at this stage the rule-set for the match-up has yet to be established, though it's hard to believe it would be under anything other than boxing rules.
Mayweather (50-0 - boxing) was last seen competing against Conor McGregor in August 2017 where the undefeated boxer coasted to victory against the mixed martial artist before a 10th round TKO.
"I want to give the people what they want - blood, sweat and tears", Mayweather told a news conference in Tokyo after reportedly flying into Japan on his private jet.
"I always wanted to display my skills outside the U.S. and be in a special fight".
Nasukawa would also offer his thoughts on the contest and was confident in his abilities to defeat Mayweather. Nobody has defeated my opponent in the past and I'd like to be the man who makes history. "I look forward to giving you guys entertainment come December 31, but my relationship with Rizin, it doesn't stop just here. I will show that to you, so please stay tuned".
"He's young, fast, [has] youth, undefeated like myself, and what the people want is excitement and that's why I chose Japan", Mayweather said.