The Voice season 9 is now in knockout rounds, and the show ushered in its latest segment with some, well, knockout performances and a knockout guest mentor. Rihanna is on episode one of her four-stint residency on the show, and while some may have doubted whether or not the ANTI singer would be able to pull off actual singing advice, she proved to be one of the more effective mentors this show has had in some time.

When it came to the knockouts, where performers can show who they truly want to be by picking the songs all by themselves and executing them solo after the always-frustrating battle rounds, episode one of the knockouts showed some surprising hands from certain contestants. A few early frontrunners fumbled with poor song choices and arrangement choices, and a few dark horses are moving through to the live shows.

How did it play out?

Blaine Mitchel, "Hold Back the River": This song is quickly becoming a staple on singing competition shows for rockers to show their "alternative" side. Thanks, James Bay. After losing to Blind Joe last week and being saved by Adam, it was Blaine Mitchell's turn this week to see if he could hold a candle against favorites Andi & Alex. Blaine finally broke out with this track, showing a unique, mildly throaty tone that we hadn't fully heard from him before.
Andi & Alex, "Stupid Boy": There's something really magical when twins Andi & Alex sing together and harmonize, so when the stakes are this high, maybe it's not the right time to start singing solo. Sure, those harmonies could get a little tired and the interplay between the solo verses and textures in the choruses. Alex had taken most of the solos before, and that was probably for the best. Andi's voice is airy and pretty but lacks the dramatic dynamics that you need at this point in the competition.
Who technically won the knockout? Blaine Mitchell gets to move on to the live shows. He broke out this week, finally giving it his all, and he's a natural fit for Team Adam.
Who should have won the knockout? Blaine showed up this week, and Andi & Alex fell flat, so Adam made the right choice. Plus, it felt like he never really knew what to do with the twin girls, so it's for the best that he stuck with the sort of rocker he's comfortable working with.

Braiden Sunshine, "Feeling Good": Braiden Sunshine has been a bit of an awkward dark horse during this season, but all he apparently needed was a makeover courtesy of Gwen Stefani and Rihanna. With his hair slicked back and his Harry Potter glasses in the bin, Braiden exuded confidence onstage for what felt like the first time during this performance of Michael Bublé's version of "Feeling Good." He's a baby crooner and handled this song like a baby crooner pro. This is a dynamic and hard song, but he maintained control and finally broke out this week, just at the right time.
Ellie Lawrence, "Cool for the Summer": Ellie Lawrence's tryout performance of "We Don't Have to Take Our Clothes Off" has been one of the big stunners of season 9, so she should have been an easy win for this battle. But, like Demi Lovato, she does the best with ballads, and she stumbled hard on this song. Long gone were those cool tones, instead she warbled her way through this song. Ellie was an early favorite, but maybe she peaked too early.
Who technically won the knockout? Braiden Sunshine is peaking at the right time, and in a shocker, he just slaughtered Ellie in this performance.
Who should have won the knockout? Ellie's poor song choice did her in. This could have been a really tough battle, but it wasn't. Gwen's choice was easy, and she made the right one.

Barrett Baber, "Colder Weather": This Zac Brown Band hit is one of modern country's prettiest songs, and this performance from plane crash survivor Barrett Baber reflected that. He's voice is missing the deep Southern tones that Zac Brown brings in to the original, but his performance still hit all the right emotions and notes. He has a place in modern country, and this performance made that clear.
Blind Joe, "Mamas Don't Let Your Babies Grow Up to Be Cowboys": Blind Joe's best asset is his personality, which he's injected in to all of his performances throughout his various honkytonk-style shout outs. For this performance, Blake and Rihanna advised him to sing straight and cut those out, and thus, all the magic of Blind Joe was also cut out. This performance was vocally fine, but the nerves got the best of him.
Who technically won the knockout? Barrett Baber is a more established performer and a more comfortable vocalist, and that helped bring him into the next round. Vocally, these guys are pretty much even, but being an artist is so much more than that, and Barrett had that edge.
Who should have won the knockout? Blind Joe held a unique space on The Voice, but his time was up. Barrett is more seasoned, and that'll help him out in the live shows.

Madi Davis, "A Case of You": This Joni Mitchell song is just dripping with emotions, and Madi Davis nailed every single one. This song is filled with dynamics, and moments that are small and intimate and massively lovelorn. Madi was able to pull them all off, and she navigated the winding map of this song like an old pro. Madi has been a little quiet this season, but she broke out here and showed that she's the kind of "other" singer Pharrell is looking for.
Amy Vachal, "A Sunday Kind of Love" Amy Vachal is a singer-songwriter from Brooklyn, and she's used to performing behind her guitar. For her performance of this Etta James classic, she ditched the guitar, and it seemed like she ditched her confidence with it. Rihanna and Pharrell emphasized the emotions of the song in her rehearsals, and she brought a little of that to the knockout performance, but she never fully dove in to the song. Her vocals were pretty, of course, because he voice is inherently good, but this performance was lacking a little something.
Who technically won the knockout? Madi Davis nailed the emotions of her song, compared to Amy Vachal who couldn't fully commit. Pharrell was pulled in by it and moved her on to his team for the lives.
Who should have won the knockout? Madi Davis did do better in this performance, but the coaches are all so enchanted by Amy Vachal. After she was discarded from Team Pharrell, both Adam and Blake pressed their buttons. Those dudes just can't resist a pretty girl with a guitar. After a little contemplation, she went on the ever-popular Team Adam.

Chance Pena, "Demons": Chace Pena took this bombastic, angsty song and gave it a sort of High School Musical makeover. His vocals were solid, but his intonations and passions were just a little off. He couldn't really fully commit to this vocal and the passions that come with this Imagine Dragons anthem. But, he's only 15. He may need to go through some things before he can unleash his "Demons."
Ivonne Acero, "Piece of Me": Ivonne has had quite the ride on The Voice. She didn't get past the auditions in season 8, she got cast off Team Pharrell in the battles and now has found life again on Team Blake. She channeled that struggle into her performance of this Katy Perry hit, toned down with plenty of piano backing. Those emotions came through, and she worked the ebbs and flows of this song like a girl who really has come out stronger on the other side.
Who technically won this knockout? Ivonne Acero shook her nerves away once again and channeled all of her passions into this performance. She nailed the rising and falling notes that Perry brought into the original and produced a stunning performance.
Who should have won the knockout? Ivonne nailed this one. Chance is just a little too green; he needs life experience before he can really make it as an artist.

Jordan Smith, "Set Fire to the Rain": Oh goodness. We get an Adele cover. As we all know, she's not an easy one to cover. But, if anyone on season 9 of The Voice has a voice that can even attempt Adele, it's Jordan Smith. He hit this screeching high note at one point that just blows your hair back, in the best way possible, of course. He's a dynamic performer with the sort of surprising presence that doesn't come along all that often.
Viktor Kiraly, "If I Ain't Got You": Viktor Kiraly, a pop star in Hungary, took this Alicia Keys song and really jazzed it up. Like Jordan, he played well with the dynamics of this track and worked it like the old pro that he is. His performance was a little cooler, compared to the craziness of Jordan's Adele song, but he still nailed a glass-shattering high note and proved that he has a place on The Voice.
Who technically won the knockout? The audience, really. Both Jordan and Viktor nailed these performances, and while Jordan remains on Team Adam because he had no missteps (while Viktor had a few tiny bumps), this was a poor matchup because both these men can go far.
Who should have won the knockout? That one is hard to say. Viktor may have more star power, but Jordan has the surprising, awe-inspiring voice. Either way, both men move on. Viktor was stolen by Gwen Stefani.