Matt Hardy doesn't sound too confident about CM Punk's UFC debut ...
Hardy spent years in the squared circle with Punk -- and got to know the guy pretty well before Punk left pro wrestling to become an MMA fighter.
Now, with Punk set to make his debut at UFC 203 later this year, we asked Hardy for his take ... and it's less than optimistic.
By the way, Hardy has some fightin' of his own to do when he squares off with his brother, Jeff, Tuesday night at TNA's "Hardy vs. Hardy: The Final Deletion."
Watch the video ... it's bizarre in a hilarious way.