Travis Kelce Calls Mike Tyson's Bare Ass 'The Funniest S*** Ever'

Like millions of others across the globe, Travis Kelce spent a portion of his Friday night staring at Mike Tyson's bare ass ... and he said this week the sight was "the funniest s*** ever!!"

Taylor Swift's boyfriend broke it all down for Jason Kelce on the brothers' latest episode of "New Heights" ... explaining he got a real long look at Tyson's rump just ahead of the boxing legend's big fight with Jake Paul -- as his Netflix stream paused on the now-infamous locker room moment.

The younger Kelce said his first reaction was laughter -- and then he said he whipped out his phone to send the scene to "f***ing everyone" so they could tune in.

For Jason's part, he admitted the surreal visual was actually what drew him to change the channel to the spectacle ... saying the shot of Tyson's derriere gave him a good idea of what was about to go down.

"I didn't think Mike was going to win before," Jason said, "but I knew when I saw those cheeks he wasn't going to win."

"Lose your glutes, lose your game. He got an old-man ass in that photo!"

After a good laugh, the two praised Paul for his efforts -- shouting out his Ohio roots.