Indie-pop duo Tegan and Sara got a little career boost this week from an unlikely source: mega-selling superstar Taylor Swift.

The identical twin sisters joined Swift at her Los Angeles concert on Tuesday night for an energetic rendition of "Closer," the first single off T&S's latest album "Heartthrob" - and if the majority of Swift's fans in the audience didn't know who they were before (an entirely feasible possibility), they certainly did by the time the show was over.

"The reason why I've brought you a special guest performer tonight is because...I really, really love this artist's music," said Swift in her intro. "I think that this album is one of my favorites of all time. If you've ever had your heart broken you need to have their album. I just feel like, I feel like all of us in here just need to get closer. I just want us to get closer, you know?"

Of course, Tegan and Sara are just the latest guest performers to make an appearance during Swift's current tour, with Carly Simon, Tim McGraw, Sara Bareilles and Train also among the artists to join her onstage.

Check out the full "Closer" performance in the video below and let us know what you think in the comments.