The audience reacted with squeals of delight when Swift brought her mega-star friend on stage to perform a duet of his hit song, “Baby,” with her.
And the crowd went wild.
Their song choice doesn’t come as a surprise, however. According to Billboard, Swift covered Bieber’s “Baby” during her shows in Montreal and Toronto in July.
Swift is currently on her “Speak Now” tour, which wraps up at Madison Square Garden in November. For more details on Swift’s show, head over to Billboard.
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Sure, it was a much tamer surprise than Swift’s recent wardrobe malfunction, but listen to those explosive tween screams — could this be the cause of yesterday’s earthquake?
Check it out below: