Kelly Clarkson hit the stage again with another one of her classic covers last Sunday. American Idol's first winner graced Pittsburgh's First Niagara Pavilion stage with a stunning rendition of Rihanna's "Stay." 

The singer has been covering more songs on her current "Piece By Piece Tour," according to Billboard. As Clarkson explained, the songs they cover on a nightly basis aren't picked before each show in order to keep up fan interaction. 

"We do a fan request every show, letting someone in the audience pick a song for us to cover," the celebrity told Entertainment Tonight. "It's a lot of fun for me and the band because the shows can become monotonous, and this keeps us on our toes."

Last week, Clarkson showed homage to Nick Jonas by covering his hit song "Jealous."  

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