After the show, Patrick tweeted, "@taylorswift13 Thanks for having me onstage! That was amazing!"
Check out the video of their performance below!
Even though she's a little bit country and he's a little bit rock and roll, this collaboration should come as no surprise! Taylor is a longtime fan of Fall Out Boy. Back in 2011, she covered the rock band's popular hit "Sugar We're Going Down" during a concert on the Speak Now Tour in Chicago, the band's hometown. She has also tweeted about loving Fall Out Boy's latest radio single.
I've listened to "My Songs Know What You Did In The Dark" by @FallOutBoy 43 times today.- Taylor Swift (@taylorswift13) March 26, 2013
Patrick doesn't hide his support for Taylor, either! He often tweets fans that he listens to her music and even recently said he'd be down for an on stage collaboration with her.
Taylor is currently on her RED Tour, while Fall Out Boy will be hitting the road on a North American tour this fall.