While John Mayer recently opened up to Rolling Stone and said he was humiliated by Taylor Swift in her song "Dear John," the two stars accidentally bumped into one another on Tuesday night at Tower Bar in West Hollywood.

According to Page Six, Swift entered the spot and was about to be seated when she noticed that Mayer was dining with a friend nearby.

"Taylor very visibly— in front of the entire restaurant— demanded to be moved to the other side,” a source on the scene said. “The bar’s usually an oasis of calm and privacy for celebrities and power players, but this was drama central.”

The bad blood between the two is palpable.

"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 sings in "Dear John," from her 2010 album Speak Now.

Mayer got the point.

"It made me feel terrible," he says in the new issue of Rolling Stone. "Because I didn't deserve it. I'm pretty good at taking accountability now, and I never did anything to deserve that. It was a really lousy thing for her to do."

He said the whole thing was somewhat surprising.

"I never got an e-mail," he says. "I never got a phone call. I was really caught off-guard, and it really humiliated me at a time when I'd already been dressed down. I mean, how would you feel if, at the lowest you've ever been, someone kicked you even lower?"