Kelly Clarkson forces Blake Shelton to take a lie detector test on The Voice

Blake versus Kelly. Kelly versus Blake. It is one of the greatest rivalries of our time — er, of the last few seasons of The Voice, at least. Coaches Blake Shelton and Kelly Clarkson (pals in real life) love to bring a little healthy competition to the big red chairs whenever they're coaching together, and season 23 — Blake's last — is no exception. Their playful ribbing is now baked into the DNA of the show. Usually, Blake's teasing Kelly for having no knowledge of country music (which isn't true) or for talking way too long (okay, that one's fair). Meanwhile, Kelly gets on Blake for not being up to date on music both new or sometimes iconic (this season, he didn't know Joni Mitchell's "Both Sides Now") or for lying to contestants during his pitches. And in Tuesday's episode, Kelly decides to put the latter to an end — by bringing out a lie detector test.

After contestant Chloe Abbott finishes up her rendition of The Bee Gees' "How Deep Is Your Love" and gets Chance the Rapper to turn his chair around for her, she chats with the coaches about what she does outside of performing — she's a track and field athlete training for the 2024 Olympics.

When she mentions how tough the training is, Blake interjects: "I know because I've been training for the U.S. curling team for a couple of years now." Kelly calls bull. "Is anybody else just sick of Blake lying?" she asks. And why, wouldn't ya know, there's host Carson Daly on stand-by with a lie detector test. Kelly and Carson get to ask their buddy some hard-hitting questions, like, did he block Kelly this season? He says no, but the lie detector says he lies. Is Kelly Blake's favorite coach? Blake says yes — but friends, he lies. And finally, Carson asks, "Did Gwen [Stefani] marry you out of sheer pity?" Blake responds, "probably, yes." Finally! Some truths! Is it all a little cheesy? Sure! But that's what The Voice is all about, right? Okay, no, The Voice is actually about singing and performances, but this is fine, too, I guess.

nbc Carson Daly brings out a lie detector test

nbc Blake Shelton

The lie detector

The Blake/Kelly rivalry is always better when it's about the contestants and not scripted bits anyway, isn't it? Well, we get a little of that in this fourth episode of Blind Auditions, too. Kelly and Blake go head-to-head for two contestants here. The first is Marcos Covos, a Spanish-language singer who gives a passionate performance on Selena's rendition of "Tu Solo Tu." Kelly's known for grabbing Spanish-language singers for her team, so it's no surprise that she turns. It is, however, a little surprising that Blake pushes his button at the last second. Kelly can't believe she has to fight Blake for Marcos, but in the end, Blake doesn't pitch too hard for the singer. He admits that he knew he didn't have a shot, but just wanted to annoy Kelly a little. Marcos joins Team Kelly.

The real battle, however, is for country/americana singer Mary Kate Connor. The 17-year-old performs "Stars" by Grace Potter and the Nocturnals and both Blake and Kelly want a shot of getting her on their team. Kelly praises "how beautiful and tender" Mary Kate's voice is, and Blake tells her that he loved the mix of her "soft and angelic" voice with the Appalachian sound she has going on. It doesn't matter that Blake doesn't know the song or forgets where Mary Kate said she was from — Mary Kate only wants to be on Team Blake. Kelly takes the loss and later admits that it's just the power of Blake on this show.

"Don't tell him I said this, but he is, like, The Voice. He's, like, the king of The Voice." They may enjoy teasing each other on air, but you can tell it's all in good, friendly fun. Kelly's really going to miss her sparring partner once he's gone. "He will be missed by everyone," she says.

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