John Mayer dusted off an old track this week.
The "New Light" singer performed "Half of my Heart" to a packed house at Detroit's Little Caesars Arena on Wednesday (March 22) to the surprise of many, since it's a song that features ex-girlfriend Taylor Swift. The "Anti-Hero" singer provided vocals for the track in 2009, which is around the time the two were romantically linked. A year later, however, their relationship reportedly took a turn for the worse when Swift released "Dear John," a break-up anthem detailing her experience dating an older man. At the time, Swift was 19 and Mayer was 32.
Fans in Detroit were excited, to say the least, about Mayer's solo performance of the iconic song. "John Mayer played my favorite song of his last night for the first time in years. I cried. This song means so much to me," one user wrote on Twitter. In the video, the crowd played the role of Swift in the song, singing "Can't keep loving you" as Mayer strummed along on the guitar. "Gave me chills," another user wrote.
"Dear John" isn't the only time Swift allegedly acknowledged her relationship with the Sob Rock singer, however. On her recently released album, a bonus track called "Would've, Could've, Should've" hints at their relationship with the lyrics, "And I damn sure never would've danced with the devil at nineteen," she sings.
Swift's songs didn't go without a rebuttal, though. On Mayer's "Paper Doll" released in 2013, he sings, "You're like 22 girls in one/ And none of them know what they're running from." He also called her out publicly in 2012 on her "cheap songwriting" on "Dear John," Billboard reports.
John Mayer's "Solo Tour" continues this weekend, with performances in Nashville, Cleveland and Atlanta.