Radio disc jockey Howard Stern is usually the one shocking fans, but the 57-year-old found himself getting quite a surprise when singer Sergio took the stage on Monday's America's Got Talent premiere.

"My dream is to be a recording artist. My voice can be sweet, but it's strong and firm. My voice can't be defined," the contestant -- who billed himself as "Simply Sergio" -- admitted on Monday's Nick Cannon-hosted episode. "This is the moment that Simply Sergio has been waiting for his whole life."

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Taking the stage, Sergio made sure to compliment judges Stern, Sharon Osbourne and Howie Mandel. "You're cool. I like you," he told new judge Stern, who has vowed to be AGT's "strict judge."

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When the 47-year-old singer and dancer started off his routine to the tune of "The Girl from Ipanema," the judges were unimpressed. "That was dreadful of course, you know that, don't you? You're a nice enough guy, I don't know what you're doing here," Stern told the contestant, before he begged Stern to let him sing another number.

Sergio sure made good use of his second chance, blowing away the shock jock, Osbourne and Mandel with an unexpected operatic version of "God Bless America." (Watch a clip above)

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Stern was so moved that he leapt from the judges' table to give the singer a warm hug. "Thank you, sir, for giving me a second chance. God bless," Sergio told Stern.

Find out if Simply Sergio earned a ticket to America's Got Talent's Las Vegas round in the audition clip above!

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This article originally appeared on America's Got Talent: Howard Stern Blown Away By Opera Singer Sergio