Barbra Streisand told ET all about how her collaboration with Melissa McCarthy came together for Babs' duets album, Encore: Movie Partners Sing Broadway.
"She was delightful!" Streisand gushed. "Just so funny."
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Of all the celebs Streisand called on to join her on the album, McCarthy might have been the most starstruck
"I heard you had a Starbucks in your house," McCarthy joked in a clip. "And all the employees have to wear cashmere."
While McCarthy shines under Streisand's direction, the Ghostbusters star was a bit out of her element in the recording booth.
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"She does at times sing fantastic," Streisand said. "And then at other times ... My point is, you know, she is not a professional singer."
Encore also features collaborations with Seth MacFarlane, James Brolin, Alec Baldwin, Antonio Banderas, Hugh Jackman, Jamie Foxx, Patrick Wilson, Chris Pine, Daisy Ridley and Anne Hathaway.