Melvin Gordon went head to head with his Uber driver over who's going to win Sunday's Wild Card matchup between his Chargers and the Baltimore Ravens ... and the guy didn't have a clue who he was talking to!
The video's hilarious -- the Chargers stud RB playfully goads his friendly driver to make predictions on the game and ends up getting some spicy trash talk out of him ... especially about Philip Rivers.
After praising Ravens QB Lamar Jackson and basically telling Gordon the Chargers QB sucks, he adds .