Gotta hand it to those rockin’ old dudes in the Rolling Stones — they can still attract the foxy young females.

First Katy Perry joined the Stones on stage for “Beast of Burden” in Las Vegas, now country superstar Taylor Swift has gotten in on the fun.

The 23-year-old singer joined Mick Jagger and company at their Chicago concert at the United Center Monday (June 3), regaling the audience with “As Tears Go By.” Check out all the pictures here.

Swifty tweets of the encounter that she and Mick are “friends forever” and “Filing this under ‘never in my wildest dreams’.Thank you @RollingStones for inviting me to Chicago to sing with you.”