Mickey Rourke tells TMZ Sports ... Donald Trump is a "garbage can president" -- and he'd gladly protest with the NFL kneelers as a way to stick it to our "sh**ty" Commander in Chief.
"The Expendables" star was at Ago on Saturday night when we asked him about the LeBron James vs. Donald Trump beef ... and where he stood.
That's when Rourke unloaded on POTUS -- and made it clear he's pissed at the way Trump has treated NFL stars like Colin Kaepernick, who took a knee during the national anthem to shine a spotlight on police brutality against minorities.