Reports said that the globally successful 19-year-old took a three-minute break after the on-stage fracas before returning to sing Boyfriend and then Baby.

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With palm trees framing the stage and singer Lee Greenwood on hand to sing "God Bless the U.S.A., " supporters cheered Mr. Ryan's arrival in Florida.

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Michael, wearing sunglasses and dressed in black leather, came on stage in front of 80, 000 people to sing his 1990 hit Freedom.

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Karaoke fans will sing along to scrolling lyrics on screen while their avatar performs the song on stage with a full complement of stage props, backup band and an adoring audience.

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