Ariana Grande is shaking things up as a judge on the latest season of The Voice — so much so that there are rumors her casting may lead to a major change in the show: the firing of longtime judge Blake Shelton.

Shelton served alongside Christina Aguilera, Adam Levine and CeeLo Green as judges when The Voice debuted in 2011.

While the rest of the inaugural cast has since moved on, Shelton is currently in his 21st season mentoring competitors. With eight wins to his name, Billboard dubbed him the most successful coach.

However, an anonymous source told Radar that his position is tenuous. According to them, producers believe the "thank u, next" superstar will act like a lightening rod and attract other current stars who would appeal to younger viewers.

"Blake is great but he is not in Ariana’s league," the source alleged.

“It is time for a shake up," a Hollywood agent agreed. "The only way the show remains fresh is by constantly evolving. Huge stars that wouldn’t even consider joining the show a few months ago are now thinking again, thanks to Ariana.”

Shelton caught onto the rumors and jokingly called Grande out via text message, which she then shared in an Instagram post.

The screenshot of their texts begins with Shelton sending a link to a story about his rumored firing. "Thanks a lot Ari," he writes underneath the story. "Thanks a f--kin' lot." Grande cheekily replies by "heart-ing" both of Shelton's messages.

Fans who scrolled through several photos in a slideshow on her Instagram account found the exchange. You can check it out yourself below, and as Katy Perry noted in the comments, you're looking for the last slide.

Shelton and Grande are facing off this season against fellow judges Kelly Clarkson and John Legend. (Grande replaced last season's judge Nick Jonas.)

At the time of her hiring, People reported that Shelton was looking forward to facing off against the hit-maker. Why? "Because it's somebody new for me to beat," he said.

"The easiest defeat of my career was Nick Jonas," he added. "So I'm looking for a challenge. I think Ariana could be a challenge. I'm looking forward to beating her though."

Based on their joking exchange, it's clear that Grande is fitting in with the cast. What remains to be seen is if she'll be able to grab a win in her first season on the competitive show.

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