's season 21 Blind Auditions — and that means it's time for the Battle Rounds to begin!On Tuesday night, viewers got a sneak peek at how the competition continues next week, when the coaches introduce their teams to their celebrity advisors — Jason Aldean for Team Kelly Clarkson, Kristin Chenoweth for Team Ariana Grande, Camila Cabello for Team John Legend and Dierks Bentley for Team Blake Shelton — and pair up their singers for a round of show-stopping duets.( fans will have to wait until the