Play video content EXCLUSIVE DECEMBER 2016 TMZSports.com

Ex-NFL star Jamal Anderson walked into a gas station convenience store and whipped out his penis in front of the clerk ... according to police in Georgia.

Suwanee PD got a 911 call early Wednesday morning from the clerk at a QuikTrip. The clerk reported a black male had walked into the store early Wednesday morning, slurred something and started handing over money. He started walking around the store. A short while later he walked up to the clerk and took out his penis and started masturbating.

That's when the clerk speed dialed police.

Officers arrived and spoke to the former Falcons great ... who they say appeared intoxicated, and told them he'd been dropped off by friends. The clerk did not want to press charges, so cops tell us they merely issued a ticket for criminal trespass.

Anderson is now banned from the QuikTrip, and if he returns he'll be arrested on the spot.