Now that the coaches' teams are all full with Blake Shelton, Adam Levine, Pharrell Williams and Gwen Stefani happy with the dozen of singers that make up their squad, it is high time to have these contestants clash on stage in the Battle Rounds.

In a set of teasers showing the preparations of each team for the battles that kick off on Oct. 12, Adam's team is seen working with the legendary John Fogerty, who is "very excited" about the bounty of talent in the show.

The clip shows that Viktor Kiraly will be pitted against Cassandra Robertson. Amanda Ayala will have to go toe to toe with Shelby Brown while Jordan Smith and Regina Love will be on the same stage with the same song battling for Adam's nod.

The rest of "The Voice" season 9 pairings in the Maroon 5 vocalist's corner include Dustin Monk vs. James Dupre, Manny Cabo vs. Keith Semple and lastly, twins Andi and Alex vs. Chance Pena.

Meanwhile, with the help of country singer-songwriter Brad Paisley, Blake will hone the skills of the members of his team. In "The Voice" season 9 Battle Rounds, he chose to have Tyler Dickerson and Zach Seabaugh square off. Barrett Baber and Dustin Christensen make up another battle.

Krista Hughes will take on Chris Crump while Blind Joe will tackle Blaine Mitchell. Emily Ann Roberts and Morgan Frazier will battle it out too as well as Cole Criske and Nadja Nicole. In the behind the scenes clip, the group seems to be having fun getting their makeup done and getting to bond.

Team Gwen will be assisted by Selena Gomez going through "The Voice" season 9 Battle Rounds. Gwen's battle pairings include Alex Kandel and Kota Wade, Ellie Lawrence and Tim Atlas as well as Korin Bukowski and Chase Kerby.

Braiden Sunshine and Lyndsey Elm make up another exciting pair. Jeffery Austin will be in a singing showdown with Noah Jackson while Hanna Ashbrook will battle Summer Schappell.

Lastly, Team Pharrell rehearsals will be graced by Missy Elliott, who gushed about the group's listening skills on top of their amazing vocals. In choosing his top 12, Pharrell decided to have Evan McKeel and Riley Biederer clash. Ivonne Acero and Siahna Im will fight to stay too.

Also, Celeste Betton and Mark Hood as well as Daria Jazmin and Darius Scott will be in an epic vocal face-off. Amy Vachal will take on duo Jubal and Amanda while Madi Davis is pitted against Sydney Rhame.

By the end of the Battle Rounds, only 24 people will continue their journey to become the winner of "The Voice" season 9. Eight contestants whom their coaches do not pick get a chance to stay on the show via Steal.

"The Voice" season 9 Battle Rounds start on Oct. 12.