Tyron Woodley Explodes On Kelvin Gastelum, 'I Will F**k You Up Right Now'

Tyron Woodley did NOT take kindly to Kelvin Gastelum calling for a rematch -- and has this message for the middleweight fighter, "I will f*ck you up right now."

Remember, Gastelum came into the TMZ newsroom earlier month for the "UFC Roundtable," and told us he would love another crack at Woodley, after losing to Tyron in 2015.

"Ever since then we've gone back and forth," Gastelum said ... "I've called him out multiple times. But, ultimately we respect each other. I think it's more of a competitive rivalry, nothing personal."

Well, clearly Woodley doesn't feel the same way, because when Tyron was asked about the comments on "The Hollywood Beatdown," the Chosen One WENT OFF!

"Kelvin Fatselum? The one who fought me at middleweight when I was a welterweight and got his ass whooped when I broke my foot? The one I gave him his money back and now he's talking sh*t?"

FYI, Gastelum came in 10 pounds overweight for their fight at UFC 183 and was fined 30% of his purse. Tyron says he sent the money back to Kelvin because he felt bad for him.

But, Tyron also broke his own foot in that fight and still got the victory via split decision -- and now, he's firing back at Kelvin.

"Why you wanna get your ass whooped again? You got beat on one foot, I played games with you. You didn't land one punch. You missed weight by 10 pounds. I gave you your money back."

Tyron also takes issue with the fact Gastelum now refers to himself as "The Middleweight King."

"You have never fought for a middleweight title and won my man. What are you the king of? You the King of Qdoba. You the King of Chipotle. That's what you the king of."

"I don't have no love for you G. I ain't got no pity for you," Tyron continued.

"I was respectful, I didn't bash you when you missed weight. And, now you wanna talk sh*t about me? I will f*ck you up right now. I will f*ck you up in the Octagon. You garbage, your whole squad is garbage."