Sabrina Carpenter Welcomes Kacey Musgraves At Outside Lands

Sabrina Carpenter is already dominating pop charts around the world this summer, but she got a little extra help from a friend last night (Aug. 10) at the Outside Lands festival in San Francisco when she welcomed Kacey Musgraves for a surprise appearance.

The pair performed the 1966 Nancy Sinatra classic “These Boots Are Made for Walkin’,” for the first time, trading vocals while Carpenter kept the beat on tambourine. “She won’t come out unless you’re very loud,” Carpenter told the crowd beforehand. “We look so good, oh my god!,” she marveled once Musgraves arrived. “Should we sing our song?”

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For Carpenter, who has scored No. 1 hits this summer with “Espresso” and “Please, Please, Please,” Outside Lands was her first time headlining a festival (albeit filling in for the previously announced Tyler, the Creator, who dropped off the bill without much explanation in June). Her highly anticipated new album, Short n’ Sweet, arrives Aug. 23 and will be supported by a huge North American arena tour this fall, beginning Sept. 23 in Columbus, Oh.

Musgraves starts her own North American arena tour Sept. 4 in College Park, Pa., on the back of her latest album, Deeper Well.

Meanwhile, Outside Lands concludes today with sets from Post Malone, Kaytranada, Sturgill Simpson and Slowdive.

To see our running list of the top 100 greatest rock stars of all time, click here.