Kelsea Ballerini explains why she covered for Kelly Clarkson on 'The Voice'

Kelsea Ballerini revealed why she's been sitting in Kelly Clarkson's chair on "The Voice" this week.

Ballerini, who served as a coach for singers in season 15 and was Team Kelly's celebrity mentor in season 16, said on Twitter that it was her love for Clarkson that led to her surprise appearance in the current season's Battle Rounds.

"When @kellyclarkson calls and asks you to keep her seat warm, you put all those years of being her super fan to work," Ballerini wrote on Twitter. "Thank you @johnlegend @nickjones and ole pops @blakeshelton for making me feel like part of the @NBCTheVoice family."

"I'm forever #teamkelly... see y'all at the battle rounds!" added Ballerini in a second tweet.

Ballerini offered even more details during an interview with "Entertainment Tonight," revealing that she had only been asked to take on the role a day before she had to start filming.

"I was home in Nashville and got a text from Kelly at like 9 p.m., like 'Hey girl... I'm not feeling well. I don't have COVID, but with the protocols, (I) don't feel safe going to set, could you cover the Battle Rounds for me?'" Ballerini said. "So I got on the plane, studied everything and watched everything. Landed, hair and makeup, set, said hi to Nick Jonas and John Legend and Blake Shelton, got in Kelly's seat, and said 'Fake it till you make it!'"

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In a brief video shared before Ballerini's first appearance last week, the country singer joked that the other judges should "just pretend (she was) Kelly" and showed off Clarkson's penchant for joking with coach Blake Shelton.

Ballerini told "ET" that Clarkson was watching a livestream of the show "and picking on Blake the whole time."

Clarkson also thanked Ballerini for stepping in.

"Thank you so much @KelseaBallerini for sitting in for me while I was feeling under the weather!" wrote Clarkson on social media. "I know my team is in great hands with you!! Y'all aren't going to want to miss this!!"

Ballerini told "ET" that she "really enjoyed" her time on the show.

"I didn't have the time to get nervous, because it was so quick, and that's good for me," Ballerini said. "If I know something's coming up, I mull over it and I get so nervous and anxious, so it was actually a real blessing. But yeah, I really liked sitting in the seat, I'm not going to lie."

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