His genuine freestyle skills caught the attention of Power 106 in Los Angeles, and J Cruz had him on with Joey Badass.
In the clip below, Badass and Cruz throw out suggestions for Mack to rap about, and more often than not he seamlessly incorporates them into his freestyle.
Joey and Cruz tried to throw Mack off with difficult phrases ("Black Guys" and "Mexicans", for example). But he proved pretty unflappable.
Badass and Cruz were very complimentary after he finished.
"You made history today bro," Joey told him.
What did you think of the freestyle?