shocked fans during her Las Vegas concert when she pulled her A Star Is Born costar on stage for a surprise performance of their from the film, “Shallow.”

In the middle of her Enigma residency show at the Park MGM on Saturday, the pop icon addressed the crowd: “So a really good friend of mine… I don’t know if you know him but his name is Bradley. He made that movie A Star Is Born.”

A shows Cooper, who also directed Gaga in the film, sitting in a private area near the front of the audience. “So I’m gonna be a little chance-y,” she continued. “Yo Bradley, you wanna come up and do this one?”

Cooper agreed and made his way to the stage, where they shared a hug and she led him to the piano.

“I even got you in-ears,” Gaga, 32, said of the earbuds singers use to hear themselves in concert venues.

“Jackson never used these,” Cooper, 44, joked in reply, referencing his rebel character in the film.

Though he added, “I can’t hear anything,” Cooper seemed unfazed as he launched into a rendition of the song, which is .

Gaga kneeled on the ground beside Cooper, who sat on a stool for the song and looked down at her warmly, resting a hand on her arm as he sang.

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Gaga then played the piano for the second verse before the two came together again for the chorus.

Cooper rocked out behind her, playing an air guitar as Gaga sang the emotional ballad. He then joined her on the piano bench and wrapped an arm around her to finish out the final chorus together.

Gaga received a Best Actress Oscar nod for her role as Ally in the film, and though Cooper is nominated for Best Actor, .

“At the end of the day, he knows that he’s the best director in my eyes, and in all of our eyes as his cast,” Gaga told the earlier this month. “I know that he’s so happy that we’ve all been nominated and that the film was recognized and we all feel really, really beyond elated for the recognition.

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The movie also garnered nominations for Best Picture, , Best Adapted Screenplay, Best Cinematography and Best Sound Mixing.

The costars had never performed the song live together since production of A Star Is Born, but as Rolling Stone notes, they to do so at February’s Academy Awards. Variety reported on Thursday that will likely be part of the telecast: Kendrick Lamar and SZA’s “All the Stars” from Black Panther and “Shallow.”