Aguilera is taking a page from Levine and Shelton's book and perfecting her hard sell in the hope of nabbing this year's top contestants for her team.
"Adam's like deliciously competitive," she said. "You just see his, you know, the blood boiling because he's the best sales pitch. I mean, he's a genius sales pitch guy. ... He'll sell a used car to your grandma."
Audiences may revel in seeing her and Levine go head to head, but Aguilera insists it's all friendly competition.
"That's what was so cool about coming back this season is because there's a comfort level that we've never had before," the 32-year-old said. "That it's just like we know each other so well. We know what's going to get each other ticking or riled up, emotional. And it's cool."
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