Grande, clad in a sparkly mini, kicked off her hit track solo until Bieber appeared, sending the crowd into hysterics.
The 21-year-old pop star managed to grasp the chorus of the song, filling in for The Weeknd, but soon resorted to dancing onstage and greeting fans while Grande, also 21, continued singing after he noticeably forgot the lyrics.
“I feel really bad. I forgot the lyrics, Ariana,” he then apologized onstage. “I’ve been trying to remember them backstage for like an hour. I feel so bad. I’m so sorry.”
Grande accepted the recently roasted singer’s apology, telling him: “No one could hear — everybody was screaming too loud! It’s okay!”
The Biebs, who clearly felt awful, also apologized on Instagram, posting a photo of himself onstage with Grande and the caption: “Had fun with u Ariana, even tho I forgot all the words haha.”
Watch the awkward snafu above.
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