Taylor Swift made a surprise appearance at the Tight End University kick-off party in Nashville to perform her song "Shake It Off." ...

And here's Kelce enjoying the performance backstage: So stinkin' cute. So technically, Kelce has been on stage at a Swift ...

Taylor Swift wowed fans with a surprise performance of her track 'Shake It Off' at her boyfriend Travis Kelce's Tight Ends & Friends Concert in Nashville on Tuesday, June 24.