The Knockout Rounds are next on season 21 of “The Voice” — and Blake Shelton is already facing a “soul-crushing” decision!

In ET’s exclusive sneak peek at the Knockouts, which kick off on Monday, Team Blake’s Hailey Green and Libianca take the stage to perform a song of their choosing, in an attempt to make it through to the season 21 live shows.

Hailey kicks things off with a rocking rendition of Blake’s own song, “God’s Country,” earning massive praise from all of the coaches.

“That was brave of you to sing the one and only Blake Shelton’s song, right in front of him,” Ariana Grande raves, praising the 15-year-old’s “strong” voice.

“I’ve literally lost years off my life trying to get through that vocal, and listening to you sing that, holy crap!” Blake marvels.

“You are like a baby Janis Joplin,” Kelly Clarkson agrees. “I haven’t really heard a female in that lane since Gretchen Wilson.”

However, Libianca also puts up a powerful performance, adding her signature soul on Billie Eilish’s “everything i wanted,” despite Blake sharing that she had been struggling with the song in rehearsals. “To see you pull together and do it, that’s incredible,” her coach praises.

“It was a master class in vocals,” John Legend adds. “You had me on the edge of my seat.”

With John and Ariana leaning towards Libianca, and Kelly favoring Hailey’s unique style, who will Blake pick to compete on the live shows? Fans will have to wait until Monday to find out.

As the Knockout Rounds begin, check out ET’s complete roundup of the season 21 team rosters to follow along with your favorites.

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