Justin Bieber is a girl who not worthy of Freddie Roach's tutelage ... so says the Manny Pacquiao's famed trainer.
We got Freddie at LAX Saturday, and he clearly harbors a grudge that the Biebs was squarely in Floyd Mayweather's corner during last year's fight.
You gotta think he's pissed off Ronda, Holly and Misha, right?
