Ariana Grande gave her Miami fans a major surprise when Justin Bieber joined her onstage to perform "Love Me Harder" on Saturday night (March 28).

Justin took over the second part of the first verse, which was originally sung by The Weeknd, on the duet. While he sounded great on the mic, the "Baby" singer fumbled on the words. And although he did feel a bit embarrassed about the whole thing and apologized to Ariana via Twitter later that evening, everyone in the crowd seemed to overlook the mistake because, well, Justin's back!

The two also performed Justin's "All That Matters" and "As Long as You Love Me." And since Ariana's boo Big Sean, who's featured on "As Long as You Love Me" wasn't at the show, she took over his verse and showed that Sean wasn't the only one who had flow in the relationship.

After the show, Justin thanked Ariana for letting him crash her concert and posted a photo of the two from the show as well as some video of Arianators as he walked outside the American Airlines Arena, which you can see below.

Meanwhile, Ariana returned the gratitude and tweeted, "thank u miami babes and thank u @justinbieber!!!!!!" She also showed love for Miami, who showed their support for the Boca Raton, Fla. girl.

Ariana will be playing San Antonio on March 31 and will continue the North American leg of her tour till on April 16 in Vancouver. She will then head to Europe for that part of the Honeymoon Tour on May 14. Ariana has also recently added new U.S. dates, which you can find here.

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