T.J. Dillashaw is doubling down on his threats to beat Gervonta Davis' ass in the Octagon ... telling TMZ Sports he REALLY wants to show the boxer "what real fighting is all about!!"
T.J. and Gervonta got in an epic Twitter war last week -- trading all kinds of insults -- and actually challenged each other to a fight.
When the UFC superstar dropped by the TMZ newsroom this week ... he took a break from trash-talking Henry Cejudo to tell us he's dead serious about a future tilt with Gervonta.
"This is a guy I would love to step into the Octagon and show him what fighting is really about," Dillashaw says.
Of course ... Gervonta's never fought in the Octagon before -- so the match would take some time to come together.
But ... T.J. sounds like he's willing to wait.