Nicole Kidman on Her Lap Dance for Jimmy Kimmel

Nicole Kidman on Her Lap Dance for Jimmy Kimmel

Nicole Kidman raised eyebrows on Thursday night during Matt Damon's Jimmy Kimmel Live! takeover when she greeted Kimmel -- who was strapped to a chair -- with a lap dance. On Sunday's SAG Awards red carpet, the Oscar winner explained the move to Nancy O'Dell.

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Kidman described the dance as "impromptu," saying that she was just following the lead of another one of the night's guests.

"Robin Williams had done it before, so I thought, 'Well, why not?'" Kidman explained.

For years Kimmel has had a running joke where he ends every episode by apologizing to Matt Damon for running out of time for him. On last week's special episode of the late-night show -- nine years in the making -- Damon recruited some friends (which included Andy Garcia, Sheryl Crow, Ben Affleck, Jennifer Lopez, Robert DeNiro, Sarah Silverman, Demi Moore and Oprah Winfrey.

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While Kidman was making headlines for letting her hair down on screen, her husband and American Idol judge Keith Urban was attracting attention for staying reserved. When one Idol hopeful asked him to accompany her to the hospital, Urban responded that he'd have to bring his wife with him.

"He is so sweet," Kidman said. "I think that's really coming across on the show, too."

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