The coaches’ teams are almost full on season 21 of “The Voice” — but when a singer like Aaron Hines takes the stage, everyone has to hit their button!

In ET’s exclusive sneak peek at the final night of Blind Auditions on Tuesday, the San Antonio, Texas, native takes the stage to impress the coaches with his cover of Giveon’s “Heartbreak Anniversary,” earning one of the season’s last four-chair turns.

John Legend is the first to hit his button, and is quick to tell Aaron, “I love your voice.”

“You just sounded like you knew what you wanted to do with the song,” he adds. “You went out there and executed it beautifully.”

Aaron thanks John for his praise, adding, “I can’t tell you how many times I’ve sang ‘All of Me’ at weddings.”

The EGOT winner then prompts Aaron to sing a bit of his 2013 smash hit single, and the two harmonize on the iconic chorus.

“I’m feeling very confident,” Kelly Clarkson jokes after the moving moment, though Aaron insists: “I promise I love you, too!”

Blake Shelton tries to use the awesome duet against John later, when he makes the case for himself over his fellow coaches.

“[John] always has his artists sing his songs, because he gets paid,” Blake teases. “Congratulations, you made a little extra money today.”

With just one night of Blind Auditions remaining, check out ET’s complete roundup of the season 21 team rosters and follow along with your favorites.

Ahead of season 21, John Kelly and Blake placed a target on Ariana Grande’s back as the first-time coach this season — especially because so many of the show’s young singers idolize the two-time GRAMMY winner’s vocal talent and chart success.

“Of course she’s a threat!” John said with a laugh during their preseason press conference. “She is hugely talented, hugely successful and has legions and legions of fans that know how to use the internet and vote.”

“There’s no disadvantage when you’re Ariana Grande,” Kelly agreed. “She can’t say it. I will.”

“It’s embarrassing to follow her [onto the ‘Voice’ stage],” Blake joked of the audience’s enthusiasm for the “7 Rings” singer. “It exposes my lack of celebrity.”

As a longtime “huge fan of ‘The Voice’,” Ariana was humble about her possible advantages, but said she couldn’t wait for fans to see how her season 21 team comes together.

“I have watched many seasons and I love watching the show,” she said. “It always has the best energy. It’s such wholesome, inspiring television, and I love seeing the different voices and watching so many people start careers for themselves. It’s a beautiful, amazing thing.”

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