Grande, who was performing at the American Airlines arena on Saturday for her Honeymoon Tour, began singing her single “Love Me Harder,” before Bieber came out to join her on stage.
Bieber, 21, sang the parts originally performed by The Weeknd, but he apparently messed up a few of the lyrics. “So I feel bad, I forgot the words, Ariana,” he told the pop diva after the song ended. “I’ve been trying to memorize them backstage for like an hour!”
Grande, 21, assured Bieber that “nobody heard,” and the two went on to duet on the Canadian singer’s hit song “All That Matters.” The duo also performed Bieber’s 2012 song “As Long As You Love Me,” with Grande taking over the rap verse performed by her boyfriend Big Sean.
Later Saturday night, Bieber shared a photo of the two on stage, laughing off his minor flub.
“Had fun with u Ariana, even tho I forgot all the words haha,” he wrote.
The “Baby” singer also ignited tour rumors when he tweeted “Thank you @ArianaGrande and thank you Miami. I missed the stage. See u soon ;).” Soon after, he wrote “Great night. Loved being back on stage. Miami I’m not done yet…”
Bieber hasn’t had a concert tour since his 2012 to 2013 Believe world tour.
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