Nick Young got HEATED during a rec league championship game on Wednesday -- where he had to be held back during an on-court altercation ... and eventually forfeited the game.
The former Lakers star was hoopin' at the 1st Place Sports Complex in Chatsworth, CA Wednesday for the league championship ... and they were killin' it until things went south.
We're told Nick's team was up 14 in the 2nd half when an argument broke out over a foul call and things escalated quickly.
Some words were said and Nick got angry -- to the point where his teammates had to hold him back from a possible fight.
Eventually, we're told Nick and his team just grabbed their stuff and left the gym without finishing the game ... which was later ruled a forfeit and the title was given to the opposing team.
It's not the first time Swaggy P has been accused of losing his cool at a rec league game -- back in 2016, he was sued for allegedly beating up an opposing player at a church league game in Porter Ranch.