'AGT': Howie Mandel gives Golden Buzzer to 11-year-old discovered singing in studio audience

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It's a lesson judges Simon Cowell, Howie Mandel, Heidi Klum and Sofía Vergara learned on Tuesday's episode of the NBC reality competition, which saw an 11-year-old girl clinch the coveted Golden Buzzer after catching the judges' attention while singing in the studio audience on a commercial break.

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Before her seemingly impromptu performance, Madison Taylor Baez opened up about being a fan of "AGT" since she was 4.

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"I am the biggest fan there could be of 'America's Got Talent,' and here I am," she said.

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But instead of walking onto the stage and auditioning the old-fashioned way, Baez hid in the studio audience, blending in among the fans.

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To pass the time during breaks, members of the "AGT" studio audience get the chance to sing into a mic.

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When the mic came to Baez, her powerful rendition of "Amazing Grace" instantly made the judges crane their necks in her direction and earned a standing ovation from the crowd.

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