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Georgia football legend Herschel Walker is expected to reveal in an upcoming book that he has multiple personalities — a revelation that surprises the man who coached the 1982 Heisman Trophy winner.

"That's all news to me," former Georgia coach Vince Dooley said. "All I know is whatever personality he had when he had the football was the one I liked."

"Breaking Free" will chronicle Walker's life with multiple personality disorder, according to Shida Carr, the book's publicist at Simon & Schuster.

Carr said the book will be published in August, but gave no other details and declined to provide excerpts.

"There's some buzz out there and we're letting people know we have this book coming out," Carr told The Atlanta Journal-Constitution.

In three seasons at Georgia, Walker led the Bulldogs to a 33-3-1 record, three straight Southeastern Conference championships and the 1980 national title. He won the Heisman as a junior, then left school a year early to sign with the now-defunct U.S. Football League.

Walker went onto play in the NFL for the Dallas Cowboys, Minnesota Vikings, Philadelphia Eagles and New York Giants. He has lived in Dallas since his playing career ended.

A former Georgia teammate also was caught off guard by Walker's revelation.

"I'm probably one of his closest friends and that's news to me," said Frank Ros, who was captain of Georgia's 1980 national championship team. "I knew he was working on a book but I just thought it was about football. He does 100 things at once and always has projects going on, but that blows me away."

The newspaper said Walker could not be reached for comment.

Multiple personality disorder, also known as dissociative identity disorder, is a rare mental condition in which one person has two or more distinct personalities, according to the Merck Manual of Medical Information.