So guess who Taylor Swift invited to perform on stage with her at New York City's Madison Square Garden on Monday, Nov. 21? That'd be Johnny Rzeznik, the lead singer of alt rock hitsmiths Goo Goo Dolls. The band originated in Buffalo, which is way up north in the Empire State. But they are still technically from New York so they fall in line with Swift's tradition of inviting guests from the state in which she is touring to come on stage with her. The pair performed the band's pretty, mid-'90s smash 'Iris,' a moving ballad, which is right in Swift's wheelhouse.

Swift and Rzeznik looked like a well-matched pair, dressed all in black. She wore her sparkly, night-hued dress with knee-high boots and he was cloaked in black blazer and trousers, with super well-coiffed hair.

Swift actually allowed Rzeznik to take the lead for much of the song; she accompanied him, playing guitar by his side and contributed her vocals for the harmonies, but for the most part, she was the back up.

Overall, though, it was a subdued performance, which is what the song calls for. But Swift did encourage the crowd to wave their hands back and forth in the air, which her adoring fans obliged. As is her custom, she hugged Rzeznik after the performance and walked him off stage.

Watch Taylor Swift and Goo Goo Dolls' Johnny Rzeznik Perform 'Iris'

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