Before They Were Reality Judges, Britney Spears and Steven Tyler Shared the World's Largest Stage (Photo)

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Steven Tyler and Britney Spears onstage at the Super Bowl XXXV halftime show Jan. 28, 2001.

THR looks back at Super Bowl XXXV, when the "X Factor" and "American Idol" stars stole a smooch during their halftime show performance.

With Britney Spears now on The X Factor as a $15 million-a-year judge and Steven Tyler in his second season holding the same job on American Idol, it will be a long time before they kiss onstage again. But at the 2001 Super Bowl XXXV halftime show, they were part of an eclectic combo. 

First-time producer MTV wanted to do something different. "Having an old, white rock dude up there was too predictable," recalls MTV Networks Music Group president Van Toffler, who exec produced.

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What the 84 million TV viewers would see was a genre-busting, nine-minute set that included Spears, then 19, who had the hit album Oops, I Did It Again; Tyler, then 52, with Aerosmith; Run-DMC; Mary J. Blige; 'N Sync; Nelly; and a Siegfried & Roy-level of pyrotechnics. 

Toffler says a key reason for choosing Spears was that "she had a humongous teen girl following" that would stretch the audience demographic. He recalls Spears -- whose messy personal life would begin to take center stage three years later when she married childhood friend Jason Alexander in a quickie Las Vegas wedding -- as a real pro: "Britney has the work ethic and coachability of those Disney kids," says Toffler. "She knew how tricky the timing would be for her to be at the right place and hit her cue, and she nailed it." 

The show ended with the talent singing Aerosmith's "Walk This Way." It was the day's highlight as the Baltimore Ravens went on to a ratings-killing rout of the New York Giants.