Hayden Panettiere Does "Lady Marmalade" on "Lip Sync Battle" -- with Christina as a Surprise Guest!
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Looks like Beyonce isn't the only surprise celebrity guest popping up on "Lip Sync Battle" this season!

In a sneak peek at this Thursday's face off between Hayden Panettiere and Eva Longoria, we get a glimpse at the "Nashville" star's performance of Christina Aguilera, P!nk, Lil Kim, Mya and Missy Elliot's version of "Lady Marmalade."

Rocking a ridiculous wig, extreme makeup and one very revealing outfit, Hayden looked JUST LIKE X-Tina in the "Moulin Rouge"-themed video from 2001. Yes, "Moulin Rouge" was 15 years ago ... let that sink in for a moment.

While Hayden was slaying it on her own, she took it to the next level by having Christina herself pop up for a cameo during her performance. Longoria looked shocked!

Check out the sneak peek below. We can't wait to see how Eva tries to top this!

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