Adam thought both singers were "fantastic" but Celia is "a star" who's unique and "so much bigger than just one moment." He said she's so many things and has so much to show.
Blake told Oliv that she "literally just jumped on the radar" with the best contestants on The Voice because it was her best performance to date and she just charmed America.
John preferred Oliv's performance because she had more energy and enthusiasm towards her specific song that was thoroughly executed. John felt Celia's song choice didn't take advantage of her strengths.
Blake was up for the next Cross Battle and he chose Dexter Roberts as well as a "Team Adam" challenge. Adam then picked Andrew Jannakos to sing.
Dexter sang "Believe" by Brooks & Dunn, and then Andrew performed "Yours" by Russell Dickerson.
Blake thought Dexter made the song his own and did it justice. He thought it was "absolutely pitch perfect" and Dexter is "going to be a star."
Adam, however, argued Andrew showed off his "unbelievable" range.
Andrew shocked Kelly, and she said he's incredibly gifted and represents new country. Kelly noted Dexter represents old country.
John said he honestly preferred Andrew's performance to Dexter's because he "wowed" everyone.
The final Cross Battle belonged to John, who picked Maelyn Jarmon to challenge someone from Adam's team. Adam therefore selected Rod Stokes.
Maelyn took the stage with "Mad World" by Michael Andrews, and then Rod performed "How Am I Supposed To Live Without You" by Helene Fischer and Michael Bolton.
John called Maelyn a gifted singer, saying she made excellent stylistic, intelligent and dynamic choices.
And Adam argued the story of the night was Rod, who "took the whole house down" and shocked his former coach.
Voting opened at the end of Monday night's broadcast, and the artists with the most home viewer votes within each Cross-Battle pairing will advance to the next round.
Carson Daly will reveal the first set of results on The Voice's Tuesday night episode on April 16 at 8PM ET/PT.
In this round, Adam, John, Kelly and Blake will each be allowed one "Save" and one "Steal." The coaches will only have 10 seconds live to make a decision after the results of any given Cross Battle are announced.
An artist can be stolen from an opposing coach's team, while the "Save" allows a coach to keep a certain, beloved team member on his or her own team going forward.
Next week, the Live Cross Battles will continue on Monday, April 22 from 8-10PM ET/PT, and Tuesday, April 23 from 8-9PM ET/PT.
"In another unprecedented first, coaches could enter the Top 24 live show with uneven teams as America decides the winner of each Cross Battle," according to NBC.