50 Cent shades Floyd Mayweather after he announced he'll be fighting a 20-year-old kick-boxer next

Earlier today, Floyd Mayweather, 41, announced he will be fighting a Japanese kickboxer Tenshin Nasukawa on New Year's Eve in Saitama, Japan.

The American undefeated boxer, who has never been beaten in all 50 of his career fights, also made an announcement that he has signed with Japanese mixed martial arts promotions company RIZIN Fighting Federation ahead of the bout.

Now, his enemy, rapper 50 Cent has taken to Instagram to shade the boxer for accepting a deal to fight a 20-year-old kickboxer.

Sharing a photo of Nasukawa and Floyd, 50 wrote: 'Champ fighting a Uber driver before the IRS embarrass him again. Pay-pre-view my ass, we watching this on YouTube. ?get the strap.'