When The Sing-Off returns next week for its holiday special, it'll be without one very familiar face: Ben Folds.

Sitting in for the four-time judge on NBC's a cappella competition is Fall Out Boy's Patrick Stump, and in The Hollywood Reporter's exclusive clip, he knows he has big shoes to fill.

"Shoot! How do I fill those?" he says of following Folds, who is currently on tour. And why was he picked for the gig? "They got the other nerdy rock star that they could find!"

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Reassuringly, host Nick Lachey then teases, "Feel free to use a lot of big words that none of us understand, and we'll feel like we have Ben right there!" while fellow judge Jewel offers him a welcoming gift.

Despite the pressure to meet Folds' standards, the Fall Out Boy rocker has one particular fan he's hoping to please while onscreen.

The Sing-Off airs on Dec. 17 at 9 p.m. on NBC. Watch the exclusive clip below.

Email: Ashley.Lee@THR.com

Twitter: @cashleelee