Johnny Manziel -- Calls Reporter a 'P***y' ... Reporter Fires Back

Johnny Manziel just lashed out at a reporter -- calling the guy a "p***y" for allegedly posting a photo of the QB at an Ohio bar.

But the reporter says Johnny is misdirecting his anger ... and THREATENED to catch him in the streets.

Manziel went after sports radio reporter Will Burge -- who had tweeted a pic of Manziel along with the caption, "2 yrs ago he was a 1st rd pick...now hes unemployed watching it at a bar in Columbus b4 the Bieber concert #Manziel."

Manziel -- clearly under the impression Burge took the photo -- responded, "Should have just said it to my face instead of sitting across from us tweeting away. P***y."

Burge fired back with a promise -- "I wasn't there tough guy. But we'll see each other DT Cle soon enough."

Manziel also addressed his other critics -- essentially saying he knows he's made mistakes ... but he is who he is and it doesn't seem like he cares about changing.

"You guys act like what I'm doing is something new. I've been the same person, doing the same things since it all started."