"If I see this beady-eyed, snake-head-lookin' dude in any room, my heart rate goes up. I just want to punch a hole through his head."

Yeah, that bad.

We talked to Usman -- the 7th ranked welterweight in the world -- the day before his headlining UFC Fight Night against Demian Maia in Chile.

Kamaru says the whole division knows he's the best fighter -- even champ Tyron Woodley -- but there's only 1 guy who gets his blood boiling.

Covington.

The beef goes back ... Usman once told us C.C. had "p***y-itis," and they almost came to blows before UFC 223.

So, if Usman leaves the Octagon with a W Saturday ... you know who's next up on the wish list -- and if it goes according to plan, there will be blood.

"I just want to punch a hole through his head."