Shannon Sharpe tells TMZ Sports if Antonio Brown doesn't start shaping up and following NFL rules ... he's NEVER going to play a down in the league again!!!
"The game will go on without Antonio Brown," Sharpe says. "He needs to understand that."
Sharpe -- co-host of FS1's Undisputed -- tells us his beef with AB is simple ... he thinks the wide receiver believes he's bigger than the league -- and therefore doesn't have to abide by its laws.
Specifically, Sharpe believes Brown is dodging NFL investigators when it comes to his civil lawsuit against Britney Taylor -- the woman who alleges Brown raped her in 2018.
"He thinks he can play by his rules," Shannon says ... "We'll see how far that takes him."
Sharpe says unless Brown has a change of heart ... NO NFL team will touch him -- not now, and not EVER -- saying the game will ALWAYS find a replacement for players, no matter how good they are.
"It's been going on for 100 years -- Joe Montana, John Elway, Deion Sanders -- some of the greats. And, the game still goes on."
As for Brown ... seems he might be open to taking Sharpe's advice -- he clearly wants back in the league, working out like a mad man recently waiting on a team to call.