Maybe she just couldn't help herself. Christina Aguilera let it all hang out while performing Etta James' trademark song, At Last, at the music legend's funeral on Saturday.

At first glance, Aguilera's outfit seemed funeral-appropriate. The Voice star wore a black suit with plain black heels. But look again! The jacket to her suit had a cleavage-baring design more appropriate for a nightclub!

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James died on January 20 after a two-year battle against leukemia. "She was a force to be reckoned with," Aguilera said.

Singer Etta James has died at the age of 73 after a long battle with leukemia.

James passed away on Thursday at a hospital in Riverside, California, with her husband, Artis Mills, and her sons, Donto and Sametto, by her side, reported CNN.com.

Along with being diagnosed with leukemia in 2010, she also suffered from dementia and hepatitis C.

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"This is a tremendous loss for the family, her friends and fans around the world," said her longtime friend and manager, Lupe De Leon.