Riff Raff says he's already so impressed with the way his "cousin," Mac McClung, is ballin' out at Georgetown, he's droppin' a brand new track about the kid!
Mac has been making headlines for his insane dunks since he was in high school -- and he already posted a highlight reel jam in his 1st college game this week.
So, when we got Raff out in NYC he was all kinds of fired up about Mac -- tellin' us he's almost ready with a new song about the phenom!
"I already got one in the making for one of my albums," Raff says ... "Mac Attack! When he come through with that Mac Attack, shoot."
Mac McClung's first breakaway dunk in a Georgetown uniform was an easy one, but also a f***ing spectacular one. pic.twitter.com/TATOo4IDMc
BTW ... Riff Raff has some hoop talents himself -- and tells us he'd love the chance to join a league like the BIG3 one day.
Then, he showed off his killer handles -- and issued a warning to Harvey ... WATCH YOUR ANKLES!!!