Neymar and his Paris Saint-Germain teammates all walked off the pitch during a Champions League game Tuesday -- protesting racial language a ref used about a Black coach.
Here's the deal ... PSG was taking on the Turkish team Basaksehir at a match in Paris when the head ref went to hand out a red card over an incident during the game.
The head ref asked the other officials who should get the red card -- and the 4th official, Sebastian Coltescu, allegedly replied, "The Black guy.