Watch Ed Sheeran and Bruno Mars' amazing duet of Thinking Out Loud

Bruno Mars fans in Nashville were treated to an extra special performance when none other than Ed Sheeran made a surprise appearance on stage.

Performing a spine-tingling live version of the 27-year-old's hit song 'Thinking Out Loud', the two singers wowed the crowd, who sang along passionately, before Bruno broke out into a killer guitar solo.

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Ed's appearance at the show wasn't completely out of the blue, though.

Prior to the concert, Bruno had shared a video on social media of Ed singing him "Happy Birthday" backstage.