John Mayer claims he doesn’t have his ex, Taylor Swift, on the brain, but he certainly had a telling slip of the tongue on Wednesday.

The 41-year-old musician was performing at the iHeartRadio LIVE in Burbank, Calif., when he participated in a Q&A about his songwriting. Mayer was talking about the creative process behind his new single, “New Light,” when he said, “I was thinking about reputation.”

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This caused one audience member to let out a whoop, thinking he was referencing Swift’s recent album, "Reputation."

"Not the album, but that’s still fine,” Mayer said of Swift’s record. "That's a fine piece of work.”

He went back to explaining the meaning behind “New Light,” noting, "I started thinking to myself, there’s probably a lot of people who would be like, ‘I want nothing to do with that guy,’ but if we could only get stuck in an elevator that 30 minutes later when the fire department came and opened the door… she would have been walking away going, ‘That was nothing like I thought it would be.’”

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Mayer performed “New Light” along with his classics, “Daughters” and “Waiting on the World to Change.” He also debuted his new song, "I Guess I Just Feel Like."

Mayer and Swift had a brief but very public romance from December 2009 to February 2010. Her song, “Dear John,” is rumored to be about him and his song, “Paper Doll,” is rumored to be about her.

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