Drake and Common got into a FIST FIGHT backstage at the Grammys.

 The two [rappers] ran into each other backstage. Common was with one of his boy, and Drake was with a SQUAD OF GOONS." The insider continued, "Drake said something and Common said something back . . . there was a commotion, and I saw Drake PUNCH COMMON IN THE CHEST."

Common walked away . . . and plainclothes police escorted him back to his seat. Wow, who knew Drizzy had it in him. YMCMB!!!