03/28/2008 02:45 am ET Updated May 25, 2011

Behind Britney's Bomb: Tardy For Rehearsal, Drinking Margaritas, Refusing A Corset

Britney Spears has no one to blame but herself for her disastrous performance at the MTV Video Music Awards Sunday night. The lip-synching pop tart showed up for her big comeback late, unprepared and with a drink in her hand.

On Saturday, the day before the VMAs, Spears was scheduled to arrive at rehearsal at around 1 p.m. Our spy said, "She didn't even get to Las Vegas until 4:30 p.m. It was ridiculous . . . The production people at MTV were freaking out . . . Nobody can tell Britney what to do anymore. No one can control her. She is a mess."

To make matters worse, when she arrived in Vegas, Spears didn't go straight to rehearsals. "She went to her hotel room and ordered a bunch of food and some frozen margaritas," the spy said. "She came down, like, an hour later with a frozen margarita in her hand."

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