Blake Shelton surprised Gwen Stefani fans at her Just a Girl residency in Las Vegas, Nev., recently, appearing onstage with the star to perform their newest duet, "Nobody But You." A few days later, she returned the favor.

Stefani canceled a few of her Las Vegas shows due to illness in early February, but on Wednesday night (Feb. 19), she took the stage ready to rock. She was reflecting on "the weirdness of my whole life and career," and noted that, that morning, her duet with Shelton had been sitting at No. 1 on the country iTunes chart, when the country star rose up from beneath a set of stairs to sing the first lines of "Nobody But You."

One night later (Feb. 20), Shelton was performing in Bakersfield, Calif., for his 2020 Friends and Heroes Tour when Stefani surprised his crowd. Shelton normally performs "Nobody But You" with a video version of Stefani singing from the giant screens onstage.

"Nobody But You" is Shelton and Stefani's third recorded duet. Previously, the two teamed up for a holiday tune, "You Make It Feel Like Christmas," from Stefani's 2017 Christmas album of the same name, and for "Go Ahead and Break My Heart," which appears on Shelton's 2016 album, If I'm Honest.

"I just think it’s magical," Shelton says of the song, which has been released as a single to country radio. "I literally think it’s important of a song as I’ve ever recorded."

Shelton and Stefani released "Nobody But You," from his Fully Loaded: God's Country album, in late 2019. The two performed the song during February's 2020 Grammy Awards ceremony.

Shelton's 2020 Friends and Heroes Tour will continue through March 21; he is also coaching a new season of The Voice, which begins on Monday night (Feb. 26). Stefani, meanwhile, will wrap up her Just a Girl residency in May.

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