Young Thug and Andre Drummond Perform at Detroit Pistons Malibu Mansion Party

The Detroit Pistons were speaking slime language on Thursday night .... 'cause the team had a private party at a Malibu mansion ... and Young Thug had it gettin' LIT!!

The shindig appears to have been put on by Pistons owner Tom Gores ... with Blake Griffin posting a pic of Thugger onstage, captioned, "our owner is better than yours."

Y.T. performed one of his featured hits, "About the Money" ... and the players loved it, vibing along and rapping with him.

But, the "It's a Slime" spitter wasn't the only performance -- superstar center Andre Drummond grabbed the mic and performed some of his own music while Thugger watched.

See, Blake? Playing for Detroit ain't all that bad!!