Michael Jackson's horrific accident on the set of a Pepsi commercial in 1984 made the singer "unbalanced," according to his longtime pal David Gest. Liza Minnelli's estranged husband has been friends with Jackson since he was 18 and believes the freak accident, during which the Thriller's singer hair caught fire, changed his personality forever.

Gest says, "Michael was in so much pain after that, he became unbalanced. The trauma, and the pills (painkillers), changed him. Before then, he had a tight hold of his career. The accident didn't make Michael moody or more distant towards me, but he did become a different person. Now that those child abuse allegations are behind him, Michael is also less trusting and feels wounded. But his career vision is back and he's planning a spectacular comeback."

Jackson served as best man at Gest's 2002 wedding to Minnelli in New York City.

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(This news article provided by World Entertainment News Network)