When John Mayer performed in Adelaide at the Adelaide Entertainment Centre yesterday, he performed an acoustic rendition of Beyoncé's stunning ballad "XO" off BEYONCÉ. Never one to disappoint, Mayer's cover is impressive and the harmonica bridge will tug at your heart strings almost as much as the original song.

Earlier this month, Bey debuted the official remixes to "Blow" and "XO" by Monsieur Adi, the official DJ from The Mrs. Carter World Tour's European leg on OUT magazine's site when her cover dropped.

Watch Mayer's cover above.

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