Play video content Exclusive 9/5/19 TMZSports.com

"[Antonio Brown] is like the worst human in the world but I'm actually on his side on this one."

That's Barstool Sports honcho Dave Portnoy breaking down the drama between AB and the Oakland Raiders ... saying Oakland should have seen this coming from a mile away.

"The Raiders ... it's like, if you sign a guy you know is a punk and a jerk, you can't complain like, 'Hey, the punk jerk is acting like a punk jerk!'"

"Like everyone knew he's a jerk! You signed a jerk! Now, he's being a jerk! You get what you signed up for!"

El Pres -- who was leaving one of his famous Pizza Reviews in NYC -- wasn't done picking apart Mike Mayock and the rest of the Raiders organization for the way they've handled AB.

"He's just doing what he did at Pittsburgh at the end of his career. I don't know what the Raiders expected. The Raiders got exactly who he was advertised to be."

So, what happens now? Portnoy thinks Brown's options are extremely limited -- "I don't know where else he's gonna go. Who else would want this guy?"