Taylor Swift braved a bit of rain, waited out a little lightning, and brought out Sabrina Carpenter for a special surprise song mash-up during night one of her Eras Tour run in Sydney, Australia.

Because of the weather delay, Carpenter was forced to forfeit her opening set to make up for lost time. As a consolation, Swift welcomed her on stage during the surprise song portion of the setlist, where they started with a duet of Swift’s early hit “White Horse” before deftly weaving it together with the Evermore favorite “Coney Island.”

Before the performance began, Swift and Carpenter shared a quick story about how the mash-up came about — or, at least, the first half of it. Apparently, Swift and Carpenter have been spending their off days in Australia at the zoo, so after raving about the koalas and kangaroos (“They are so cool — so strong, so bouncy”), Swift said that one day, Carpenter mentioned that there was “a song that was really important” to her as a kid.

Carpenter then quipped: “If anyone looks up this cover, then I’m gonna be really, really upset. But I know they are. But I was nine, and ‘White Horse’ was the first ever song I learned how to play.”

This also marked Swift’s first performance of “White Horse” since she played it in Las Vegas last March and her first rendition of “Coney Island” since Atlanta last April.