Taylor Swift served up ‘Espresso’ and more with Sabrina Carpenter in New Orleans on Saturday night (October 26).

Swift teased that she was about to do something different for her acoustic set during her latest stop on The Eras Tour: sing someone else’s song. “It’s in my head,” she explained to the audience at the Caesars Superdome of her choice to bring a new flavor to the surprise song menu.

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To the delight of many, she launched into Carpenter’s huge summer hit ‘Espresso’ on her guitar. Then she paused and asked her fans a dumb question: “Is it okay if I call her and you guys can say hi?” – and grabbed a cell phone to get Sabrina on the line.

The pair of pop stars reacted a little strangely, with Swift putting Carpenter on speaker, holding him up to the microphone and asking her how long it would take her to reach the stadium.

It turns out that about five seconds later, they were on stage together, crafting “Espresso” into a three-song mashup with Swift’s 1989 vault number “Is it over now?” and another of Carpenter’s big hits, “Please Please Please.”

The highlight of Swift’s Saturday night? Having an excuse to sing the lyrics “Espresso” “I work late because I’m a singer” in a sold out stadium as it approached 11pm at night.

“She literally has one day off. She’s on tour. It’s crazy that she came to perform for us,” Swift said at the end of their crowd-pleasing duet. Carpenter left the stage, leaving Swift to wrap up the evening’s acoustic section alone at the piano, where she played a mashup of Midnights bonus song “Hits Different” and 1989 opener “Welcome to New York.”

Watch clips of their surprise performance below.

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