Currently delivering standout performances with his Las Vegas residency, Usher delivered an unforgettable show by delivering an unexpected duet with 21 Savage on Saturday night (April 15) . Sitting in the crowd throughout the show last week, the Atlanta rapper was given an opportunity to sing alongside Usher.

During a break, Usher went up to 21 Savage asking: “You like singing R&B and shit, right?” Proceeding to hand a mic to the Slaughter Gang CEO, while saying: “Let’s go, Savage. Let’s go!”

The live band at the show then broke into Usher’s 2004 Alicia Keys duet “My Boo,” with 21 Savage serving as Keys. Although he  couldn’t hit the high notes, the crowd in attendance had fun watching the two artists deliver the R&B classic.

The “Her Loss” rapper has been an Usher fan for quite some time. Back in 2016, 21 posted a video of himself singing the lyrics to the Grammy Award-winning artist’s 2004 song “Burn.” He’s also been caught belting out the lyrics to songs by SZA and The Weeknd.

Watch Usher get 21 Savage to sing “My Boo” below.