HOLLYWOOD—Well, ‘Voice’ fans, it was officially the start of the Knockout rounds on Monday’s episode of NBC’s “The Voice!”

Each contestant made their own song choices as they battled against a fellow team member. Eight-time Grammy superstar Rihanna served as the key adviser, helping each artist prepare for the Knockout Rounds.

Let’s recap some of the best performances of tonight’s two-hour episode!

Team Adam’s Andi & Alex perform “Stupid Boy,” vs. Blaine Mitchell performance of “Hold Back The River”

Twin duo Andi & Alex decided to show their diversity by covering a country song. The Indie Alternative folk artists consistently manage to put an ethereal spin with impeccably chilling harmonies.

During rehearsals, Rihanna praised the twins for how incredible they sound together, but advised them to work on being bold when singing apart.

It was apparent the twins took Rihanna’s advice to heart. During the Knockout performance, both twins revealed their strength as soloists, while still managing to incorporate their trademark harmonies.

Blaine Mitchell, who started out on Team Blake, really proved to be the resident rocker of the season. He has so much power, yet so much control. Who knew this dude has outstanding RANGE?! He did a really good job of picking a song that would allow him to showcase his vocal talent.

Blake admitted to Blaine that he screwed up for letting him go, describing his performance as unbelievable.

Pharrell says Blaine created a moment that enabled the coaches and the audience to discover more about him than they ever thought possible.

He told the twins that he wished they would have chosen a different song that would have really shined upon the discovery of Andi’s voice.

Gwen thinks the twin duo is incredible, but “Blain has something so rare that is incredible to watch.”

Adam says that the duo managed to sing separately and still shine, while the power of Blaine’s voice is amazing.

Adam ends up choosing Blaine as the winner of this Knockout. Though, I really gotta say, I am pretty sad to see the twins go. They have massive potential and are easily one of the best duos to ever hit “The Voice” stage.

Team Pharrell’s Amy Vachal performs “Sunday Kind of Love” vs. Madi Davis  who performs “A Case of You”

Madi Davis really slayed her performance by masterfully telling the story of the song by adding in gospel inspired runs. Pharrell noted during rehearsals that parts of her voice sounds like Adele, and I could totally hear that during her live performance.

During rehearsals, Rihanna mentioned that Madi has a really rich tone that she sometimes seems almost afraid of using. However, when it came to the actual night of the Knockout performance, she truly seemed to embrace all the facets to her colorful voice.

On the other hand, Amy Vachell’s song choice was a perfect fit for her sweetly prominent tone hi-lighted by jazz inflections. She seemed a bit more subdued compared to Madi, but there is an effortless quality to her voice that simply cannot go unnoticed.

Gwen says, “I can listen to both of you all day long. You are so delicious.”

Adam says Madi had a defining moment and is in awe by the growth she has made in such a short amount of time.

In regards to Amy, he says that she is one of his biggest regrets because he was not able to turn around for her during blind auditions, due to his full team.

Pharrell says, “Madi the notes you choose it’s like whoa did that just happen?!”

He also explains how Amy has brought a classic vibe to the show and is a truly interesting artist.

Although Pharrell says he feels like both of the contestants won, he ends up choosing Madi as the winner.

Nevertheless, a two steal battle ensues between Adam and Blake, but it is Adam who is finally able to woo Amy into joining his team!

Team Adam’s Jordan Smith “Set Fire To The Rain” vs. Viktor Kirlay “If I Ain’t Got You”

Ok, so this was easily the best battle of the night! It was the battle of the male powerhouse singers of the season.

Jordan can hit notes that are really just unearthly. But, it really goes beyond that. Jordan expresses during his rehearsals that it is important to him that every note he sings conveys the story being told, and of course, he does just that.

He literally pours his heart and soul into this performance while, yes, once again displaying his breathtaking upper register. There is a certain authenticity to his voice that is captivating beyond belief. Nothing feels forced or calculated.

It’s really extraordinary to watch him perform. I cannot wait to see what he will do throughout the season. He is easily a top contender.

During rehearsals, Viktor admits to being too focused on technical aspects of the song as opposed to committing to the story of the song. However, on the night of the performance, he really turns things around.

He took his time creatively emphasizing the emotions of the song, alternating between his falsetto and full voice. That falsetto though, WOW. Just Wow. Speechless!

The conviction he exudes is almost palpable. There has been so many covers of “If I Ain’t Got You,” including from Mr. Adam Levine himself, but Viktor excelled in adding his own special flavor.

Blake says everything was so good about both performances. He says he wasn’t expecting Viktor to knock it out of the park the way he did and swears that Jordan gave one of the best live vocals he has ever heard.

Pharrell describes Vikor as “clawing away like a tiger” and commends him for his ability to consistently shift gears throughout the performance.

He further commends Jordan for his ability to sing so effortlessly and eloquently.

Gwen says Viktor is so amazingly talented and was blown away by the totally unexpected notes he hit.

She further praises Jordan, saying, ” You’re a freak of nature. The way you navigate the song and take us on a journey, it was just mind blowing.”

Adam congratulates Viktor for his ability to tackle every single thing they went over together in rehearsals. “You really did your thing,” he says.

He further refers to Jordan as a unicorn, stating: “It is really a profound experience to hear you sing.”

Adam ends up choosing Jordan, but Viktor will still stay in the competition as Gwen steals Viktor, pronouncing, “I am amazed by your gift.”

Six more artists will perform Tuesday night as the Knockout Rounds will continue at 9 p.m. with a one-hour special.