Diddy's Son Justin Combs -- Thanks for Fighting for Me

Diddy's son is totally cool with his father brawling with his football coaches -- in fact ... he's thanking Diddy for the fight that cost him multiple felonies.

Justin Combs broke his silence about his dad's arrest by posting a pic of himself and Diddy ... with the caption, "I thank God for having a father that's always there for me.. Love you pops!"

TMZ Sports broke the story -- we're told Justin's strength and conditioning coach, Sal Alosi, had called him out ... saying, "I don't care if your dad's here. I'm going to treat you just like I treat everyone else." Our sources also say Alosi told Justin to leave and NOT come back for the rest of the summer.

We're told that's what set off Diddy.

Seems natural for Justin to support Diddy in the dispute -- but it leaves him in an awkward situation with the team.

At least he's wearing UCLA gear in the pic.