NFL superstar Odell Beckham is opening up on his nasty breakup with the NY Giants ... saying he felt disrespected after getting shipped to Cleveland "after everything I've done for them."
OBJ was traded to the Browns back in March ... and he says the move was like a slap in the face, claiming he kept the team relevant despite losing all the time.
"This is me being honest: This team has not been good for the last six years. Period. Even the year we went to the playoffs and everyone was talking about this and that," Odell said to GQ.