Someone got stabbed after a Chris Brown performance Monday night ... and law enforcement tells us it's yet another case of trouble following Brown and his entourage ... something cops are quietly trying to stop.
Right after Brown finished his set at a YMCMB Drake/Lil Wayne after-party at Supperclub in Hollywood ... several people who were leaving got into a fight and someone got stabbed.
The victim was taken to a hospital and he's expected to be okay.
Law enforcement sources tell us ... they didn't make any arrests because no one would ante up any info ... which leads to the bigger issue. Our cop sources say they believe this is all about Brown's entourage. Wherever they go ... someone ends up bleeding.
We're told the LAPD has privately met with club owners, trying to pressure them into blacklisting Chris and his crew, but the clubs make too much money off them so they're welcome with open arms.
As one law enforcement source put it, "When Brown and his people show, we know what's going to happen. It's a headache for us."
Brown -- who does not keep his association with the Bloods a secret -- has not been accused of instigating the violence, but cops say they know it all emanates from the singer and his entourage.
You'll recall 3 people were shot -- including Suge Knight -- during a Chris Brown performance at 1OAK last month.