In an interview with Rolling Stone magazine due to hit newsstands on Friday, the Grammy-award winner criticized the tune.

"It made me feel terrible," Mayer told the magazine. "I was really caught off-guard, and it really humiliated me at a time when I'd already been dressed down."

Swift penned the song, featured on her best-selling 2010 album "Speak Now," after the couple ended a brief romance.

Swift has never officially confirmed that it was directed at Mayer but said the subject of the tune was apparent.

"Dear John, I see it all, now it was wrong. Don't you think 19 is too young to be played by your dark twisted games, when I loved you so?" Swift wrote in the lyrics.

Mayer said he had no warning that Swift was writing the song and only learned about her feelings when he heard it.

"I will say as a songwriter that I think it's kind of cheap songwriting," he said.

(Reporting by Patricia Reaney; editing by Jill Serjeant)

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