Taylor Swift fans might still be hungover from her two-night run at the MetLife Stadium on Saturday, July 11, where Nick Jonas surprised fans as he joined Swift on stage and performed a duet of the hit song "Jealous", according to reports.

Besides bringing the U.S Women's National Soccer Team on stage, which left the crowd screaming, the 25-year old 'Bad Blood' singer gave her fans another surprise treat when Nick Jonas hit the spotlight.

On Twitter, Jonas shared the news about him jumping on stage with his longtime friend Taylor.

"Unreal feeling jumping on stage with my friend "TaylorSwift13 tonight at the #1989TourEastRutherford show in my hometown," Jonas wrote. "Thank you so much @TaylorSwift13 for having me. What an incredible memory..."

Swift and Jonas are longtime best friends and the singer is often remembered as dating Jonas's older brother Joe Jonas back in the year 2007.

Their last on stage team-up was six years ago, where Swift performed her, "Should've Said No" single during the Jonas Brothers' concert movie, "Jonas Brothers: The 3D Concert Experience" in 2009.

As Swift recalled her good old memories with the pop singer a few years back, she took her sentiments to Twitter by posting an old photo of them which showed her long, old curly hair.

"I feel all the feelings now," Swift captioned the photo. "Oh wow. Time flies when you're having fun ha," Jonas's response to Swift's tweet.

Swift's previous celebrity guests included her girl BFFs Gigi Hadid, Martha Hunt, Lily Aldridge and Karlie Kross. She had also brought world champion tennis player Serena Williams on stage.

Swift and Jonas are longtime best friends and the singer was remembered dating Jonas's older brother Joe Jonas back in the year 2007.

Now she's with her man Calvin Harris while Joe has been reportedly spotted with one of her BFFs, Gigi Hadid. Nick Jonas on the other hand, recently broke up with longtime girlfriend, Olivia Culpo.