Christina Aguilera Rocks Purple Hair on 'The Voice'

Purple reign! Christina Aguilera rocked lilac hair while judging the top nine contestants' live performances on The Voice on Monday, May 9.

The naturally blonde "Beautiful" singer, 35, styled her pastel-hued tresses straight, parted in the center with a teeny, pierced accent braid along the hairline. (Shah Karegar of the Benjamin salon colored her hair, while Chris Appleton styled it.) Keeping to the purple theme, she added a deep violet lip color.

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The mom to Max, 8, and Summer, 20 months, also worked a semi-sheer black dress with an asset-flaunting keyhole cutout at the bodice.

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That same night, Blake Shelton and Gwen Stefani debuted their new duet, "Go Ahead and Break My Heart," during the episode. An insider tells Us, "They faced each other and didn't look at the audience at all during the performance. It was like they were trying to give the illusion that to them, they were the only ones in the room. It was so romantic."

What do you think of Aguilera's latest Voice hairstyle? Tweet with @UsWeekly using the hashtag #stylebyUs!

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