Diddy's Son -- Key UCLA Players Want Him Back

Several key UCLA football players are calling for Justin Combs to return to the squad ... telling TMZ Sports the guy is a hard worker and a good friend ... and he's getting a bad rap.

As we previously reported, Combs -- a redshirt junior -- was asked to stay away from strength and conditioning drills for the rest of the summer ... prompting the kettlebell incident involving his dad.

Now, we've spoken with 3 members of the UCLA football team -- important guys -- who tell us they respect Justin and don't want him off the team.

As one player put it ... "Justin is a great friend and teammate. He works hard on and off the field. I hope he comes back."

Another player said, "He is a really cool guy to be around and I hope he does come back."

Player #3 says, "Justin works hard everyday. We go out on our own together and work on our footwork and lift weights outside of practice. I feel the coaches should let him back on the team. I know we want him back."