Nasukawa is also 4-0 in mixed martial arts with his last fight taking place in October 2017 against Yamato Fujita. Mayweather said he would retire following the bout and would not be lured back.
Despite being 41-years-old, "Money" has never slowed down.
ATP Paris Masters: Khachanov faces Djokovic in the finals
Khachanov, who won the Kremlin Cup in Moscow last month, broke fourth-seeded Alexander Zverev's serve six times in a 6-1, 6-2 win. Djokovic, who is guaranteed to take the No. 1 ranking on Monday, struggled on his serve for much of the first set.
Mayweather has teased numerous possible fights since defeating McGregor, including potential rematches with the former UFC champion or Manny Pacquiao. Stay tuned for future news regarding the rules the bout will be contested under, as well as other match-ups for the card.
When asked when Rizin FF will finalize the details of the Mayweather vs. Nasukawa fight, Sakakibara could not give an immediate answer.
Information from ESPN's Ariel Helwani was used in this report.
"As far as the weight class and rules, we'll talk about that and get it situated within the next couple of weeks", Mayweather said.
Petrol prices down by 19 paise in Delhi, diesel drops 11 paise
In Mumbai , petrol had hit a peak of Rs 91.34 hit on October 4 and diesel was sold at a record high of Rs 80.10. This came down to Rs 81.50 per litre for petrol and Rs 72.95 in case of diesel.
Mayweather will fight on December 31 at Saitama Super Arena in Saitama, Japan.
"As far as the weight class, we're not really anxious about that".
RIZIN is clearly trying to make big moves, as you don't book "Money" for a fight without spending a massive amount of just that.
"I'm older now", Mayweather said. He has made an undefeated career out of having fights play out according to his demands. He most recently has stoked the flames of possibly fighting current UFC lightweight champion Khabib Nurmagomedov.
Former Real Madrid Manager Linked With Shock Return
Despite being back to winning ways under Solari , Madrid midfielder Toni Kroos sent out a very unusual tweet after the match. Madrid are sixth in the LaLiga table, seven points behind rivals and leaders Barcelona.
Mayweather, who stopped McGregor in the 10th round past year after coming out of retirement for a $275 million pay day, had been flirting with the idea of a rematch with the Irishman or facing fearsome Russian Khabib Nurmagomedov. "But it will be a great fight that everybody will be so excited to see".