"Rock of Ages" star Hough, 23, was outed as a hardcore Phillips devotee on Wednesday's performance show -- much to the surprise of her boyfriend Seacrest, 37.
"We were backstage and you ran past my girlfriend and she sighed and blushed," Seacrest told Phillips, 21, after his performance of Dave Matthews Band's "The Stone." Added the "Idol" host: "I think I heard her say 'yummy.'"
As the camera panned to an embarrassed Hough backstage, Seacrest -- who fought through illness to host the two-hour show -- told her playfully: "We'll talk about this later, darling."
Though his performance was slammed by judge Jennifer Lopez for being "obscure and artsy," Phillips was thrilled to get Hough's stamp of approval.
"I ain't complaining! She's a gorgeous woman and Ryan's an awesome guy so they're an awesome match," he told Us Weekly backstage at Wednesday's show. "I think she got all giddy or something but I don't know. It was funny."
Phillips wasn't the only singer to get kudos on Wednesday. Joshua Ledet, who performed India Arie's "Ready for Love," earned his twelfth standing ovation of the season. Argues fan favorite Ledet to Us: "I don't ask for the standing ovations, they just come!"
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This article originally appeared on Usmagazine.com: American Idol: Ryan Seacrest's Girlfriend Julianne Hough Has a Crush on Phillip Phillips