Swoon Over Carrie Underwood’s Sheer Gown — And Her Perfectly Toned Legs

Carrie Underwood performs onstage during
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Bold beauty! Combining her love of sweet and sexy styles, Carrie Underwood rocked an epic sheer gown with lace details at the Sinatra 100: An All-Star Grammy Concert at the Wynn Las Vegas on Wednesday, Dec. 2.

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The "Heartbeat" singer, 32, dazzled in the black illusion dress by Yousef Al-Jasmi, which boasted a sheer skirt that showed off her incredibly toned legs, a detachable train, and beading from top to bottom. She teamed the steamy design with statement earrings and heels.

Carrie Underwood performs during
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But it wasn't her only sexy moment of the night! Underwood, who shares her baby boy, 9-month-old Isaiah, with her husband of five years, Mike Fisher, slipped into another style: a royal blue dress with a plunging neckline, an embellished collar, and a mermaid silhouette.

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The American Idol alum was on hand to perform at the concert, which celebrated what would have been the legendary Frank Sinatra's 100th birthday. Underwood shared the stage with Tony Bennett, Lady Gaga, John Legend, Usher, Alicia Keys, and Katharine McPhee. The concert, which was taped, is set to air on CBS on Sunday, Dec. 6, at 9 p.m. ET.

Carrie Underwood performs during
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