Deontay Wilder Says Floyd Mayweather Could Ruin Legacy With Kickboxing Fight

Heavyweight champ Deontay Wilder says you're only as good as your last fight ... and that's why Floyd Mayweather could ruin his ENTIRE LEGACY if he gets blasted in his upcoming fight.

Floyd is putting his 50-0 record on the line when he faces off against undefeated 20-year-old kickboxer Tenshin Nasukawa in Toyko on New Year's Eve in what could be an MMA rules fight (they're still working it out).

Wilder says Mayweather is putting more than his perfect record on the line because if he looks bad, his entire untouchable career could be tainted forever.

"People only remember the last thing you done. Just imagine me, I've knocked out 39 guys this is gonna be my 40th one. Let's just say this is my last fight ever, and I just go the rounds or I lose, they won't fully remember all my knockouts. That's why in boxing we must retire at the right time when we're on top."

It's an interesting point, and while other huge fighters like Muhammad Ali have looked bad in their final fights and it HASN'T affected their legacy ... that was before social media.