Grammy winner Taylor Swift surprised her 55,000-strong audience at the MetLife Stadium in New Jersey when Fall Out Boy's frontman Patrick Stump appeared on stage for her Red album tour.

The two did a duet of Fall Out Boy's "My Songs Know What You Did In the Dark (Light Em Up)" off their latest album 'Save Rock and Roll' and Swift's "We Are Never Ever Getting Back Together".

The 23-year old singer is known for surprising fans at her concert with appearances by other music super stars. Selena Gomez, Justin Bieber and Nelly were here guest stars in her previous tours.

Stump thanked the singer via Twitter after the show: "@taylorswift13 Thanks for having me onstage! That was amazing!"

Meanwhile, Rolling Stone reported that Swift is already looking forward to do a follow-up on Red.

"The floodgates just opened the last couple weeks," she said regarding her songwriting process.

Swift is keen on another collaboration with artists that she wants to work with on her next album.

"I really loved collaborating," she said. "You work with a lot of different people and you find the people you have this dream connection with in the studio. I know those people and I know the ones I want to go back to. But I also have a really long list of the people I admire and I would really love to go and contact. So that's kind of where that is."

For her fourth studio album Red, Swift experimented with pop collaborations. However, she clearly pointed out that she's not looking to repeat what she did for Red and did not reveal what she's likely to do with her next record.

Fans will just have to wait what Taylor Swift has in store for her upcoming album.

Watch the video of Taylor Swift and Patrick Stump's duet below (video credit to Alexa D.):