Video: Carrie Underwood Taunts Leighton Meester

It’s not just cheaters that bring out Carrie Underwood‘s nasty side.

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At the November 10 CMA Awards, a super-anxious Leighton Meester, 24, was prepping backstage to present an award when the 27-year-old American Idol champ, who was co-hosting the show with Brad Paisley, approached her and said, “Get out there and don’t f–k it up,” reveals a source. “It made Leighton more nervous.”

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To find out what prompted the tough love taunt — and Underwood’s views on the cutthroat industry — watch the latest Hot Stuff video (above).

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Also inside the sizzling round-up, as told by Senior Editor Ian Drew: how Christina Aguilera met new beau Matthew Rutler‘s folks; who Eva Longoria spent the Thanksgiving holiday with; why Teen Mom’s Amber Portwood was reunited with her two-year-old daughter Leah and more!

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This story originally appeared on UsMagazine.com