Together, the two artists teamed for "Sidewalks," their collaboration off Abel Tesfaye's new LP Starboy. The performance marked the first time either artist had played the track live.
At first, it seemed as though Lamar's verse was the prerecorded version from the album; however, after a few lines, the rapper emerged from backstage, with the audience collectively going crazy upon realizing Lamar was in the building.
Earlier this month, Tesfaye talked with Beats 1 Radio's Zane Lowe about the Lamar collaboration.
"He's a genius," the Weeknd said. "He did it there on the spot. He'd walk around, he'd play the record over and over again… He's writing his verse in his head… He was really committing, he really put his all into it. It wasn't just a random Kendrick Lamar verse. It was something special."