Blake Shelton sent Erin Willett and Gwen Sebastian into the battle round on tonight's episode of 'The Voice.' They were paired up to sing Pat Benatar's 'We Belong.' Willett is big and bold, full of power, while Sebastian is a country singer who can hit the highs and lows. To call this battle a "toughie" for Shelton would be an understatement.

Shelton's wife Miranda Lambert mentored Sebastian, who is intense and talented. She admitted she didn't want to take away from Willett's performance, since they became close and she wants it to feel like a real concert. Uh, while that's very kind of Sebastian, it's not wise in a reality talent competition.

Willett was advised by Kelly Clarkson, who told her that she has prettiness to her voice, saying, "If you've got it, show it." Sadly, she found out that her father, who is suffering from pancreatic cancer, is not doing well. She was trying to be as present as possible, but it was obviously difficult. Despite the personal drama, Willett certainly had increased motivation to do well and to sing her butt off, since she was doing it to make her dad proud. That effectively turned Sebastian into the underdog. So how did each singer fare?

Sebastian started the song in the loveliest fashion, with her voice even but escalating throughout. Her vocals had a soothing quality. Willett showed off her softer, more sensitive side, instead of making her point by booming from start to finish. They both gave balanced, beautiful performances.

Adam Levine and Christina Aguilera thought Willett owned the round, while Cee Lo went with Sebastian, for her ebbs and her flows. But it wasn't up to them. Shelton said he wished it wasn't that good so the choice could've been easier. Stylistically, Sebastian took chances. While Willett's power cames easy, she played it safe. Shelton was still left questioning what else she could do, since he thinks she has "it."

Shelton ultimately chose Willett.

Watch Erin Willett and Gwen Sebastian Perform 'We Belong' on 'The Voice'