Taylor Swift: 'What Hurts The Most' with Rascal Flatts!

Taylor Swift relaxes on stage with Rascal Flatts during one of her last tour stops in the states on her Red Tour at Bridgestone Arena on Friday (September 20) in Nashville, Tenn.

The 23-year-old singer and the country band – Joe Don Rooney, Gary LeVox, and Jay DeMarcus, joined forces while singing their hit song “What Hurts The Most.” Check out the video below!

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“Nashville! Tonight @rascalflatts surprised the crowd and we sang ‘What Hurts the Most’!! Unforgettable! Pics tomorrow,” Taylor tweeted after the show.

During the concert, tourmate Ed Sheeran performed during her set with a cat hat on.