Antonio Brown is 6ix9ine to Shannon Sharpe After Twitter Tirade

Antonio Brown says he's quitting the NFL because the league is corrupt and has screwed him out of millions of dollars.

Brown just tweeted up a storm, saying, among other things, "Will not be playing in the @NFL anymore these owners can cancel deals do whatever they want at anytime we will see if the @NFLPA hold them accountable sad they can just void guarantees anytime going on 40m 2 months will see if they pay up!"

What he's saying ... the Patriots signed him to a $15 mil deal with a $9 mil guaranteed signing bonus. But, here's the catch. The $9 mil was reportedly spread out over the season, and he was cut after just one week, and he's not gonna see most of that cash.

But, Brown went further and took aim at the Patriots' owner, Robert Kraft, firing this shot ... "Kraft got caught in the parlor AB speculations fired different strokes folks clearly." In other words, he's saying there's a double standard for him and the NFL bigwigs. Brown saying Kraft was charged with a crime and he was not, and the NFL hasn't punished Kraft.

He's also pissed because the NFL is investigating, and while that probe continues, he's poison to every team in the league.