EXCLUSIVEAdrien Broner got DROPPED in the middle of a Miami street the other day ... after embarrassingly crashing his motor-scooter into a parked car ... and TMZ Sports has the footage.
You gotta see this ... the boxing stud was just beginning a South Beach scooter street session with friends when things went horribly wrong.
Even when he got back on the ride, the 24-year-old had problems starting it up again ... just a total disaster.
The good news? Broner and the car were unharmed.
The bad news? There's no rematch clause in the rental agreement.