Taylor Swift and Ed Sheeran's 'End Game' duet steals the show at iHeartRadio Jingle Ball

Taylor Swift was building the suspense at the iHeartRadio Jingle Ball that maybe, just maybe, her pal Ed Sheeran might join her to sing their new song, “End Game.” “Here’s where I’m gonna tell you,” she said. “There’s a huge possibility that if you’re loud enough someone might come out and join us.”

Join her he did, singing the sing-songy rap portion of the song: “And I heard about you/You like the bad ones too/Now well, when I was young, we connected/When we were a little bit older, both sprung/I got issues and chips on both of my shoulders.”

Many a Swifty (and a Sheery?) were delighted to witness the pair’s first live performance of the recently released song. Swift and Sheeran have collaborated before on the sweet love ballad “Everything Has Changed,” but “End Game” arguably has a little bit more bite. The song also features Future, although he wasn’t there for this live performance.

iHeartRadio Jingle Ball aired on the CW.

Check out how glorious James Corden is as Taylor Swift’s new backup dancer:

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