Boxer Laila Ali delivers a powerful punch to her famous father Muhammad Ali with a blockbuster new autobiography that describes the former heavyweight champ as an uncaring, self-centered dad.

Publishing sources told The ENQUIRER that in the book — “Reach! Finding Strength, Spirit, and Personal Power” — 24-year-old Laila reveals that her loveless relationship with her father was a root cause of troubles she experienced in later years.

“Laila’s dad was a hero to millions but not to her,” revealed a publishing source familiar with the contents of the book. “She suffered extreme loneliness as Muhammad Ali’s youngest daughter and she wanted to run away from home when she was only 4 years old. She grew up feeling angry and hostile. The only thing that straightened out her life was a run-in with the law. She finally learned responsibility from a group home.”

Today Laila is a successful pro boxer, a businesswoman and aspiring actress and model. But it’s clear from her book that she succeeded only by using survival skills learned during her difficult childhood as daughter of Muhammad Ali and his third wife Veronica Porche.

“Ali never discussed with his daughter what was going on in her life,” said the source. “He was too busy dealing with his own life. Laila Ali didn’t like much about her father — his Muslim religion, his big, slobbery kisses, his outgoing personality.

“He was so busy in public giving out autographs, photos and advice, he would walk out of a restaurant or a mosque and forget he had come with his kids. Then he’d eventually remember and return to gather them up.”

The child was so isolated that when she was sexually molested by a relative at age 5, and again at age 10, there was no one she could tell.

“The fondling opened the floodgates to embarrassment and shame,” the source said. “Laila writes: ‘My parents didn’t have a clue.'” Family life for Ali’s lonely daughter was already almost nonexistent, when in the mid-1980s Laila’s mother rebelled against the subservient role of a Muslim wife and divorced Muhammad for infidelity. Her father’s faith was difficult for Laila as well.

“Laila hated her father’s preaching, the prayers, the mosque, words she didn’t understand, a faith she didn’t believe in, and the women sitting behind the men,” the source said.

A few years after the divorce, in 1993, a troubled Laila was arrested for shoplifting and spent three months in detention. After her release, she moved to a group home where she made friends and got her life together. In 2000 she married boxer Johnny “Yahya” McClain, became a pro boxer herself and is still undefeated after 11 bouts.

“Laila decided to tell her story to inspire anyone else struggling with self-doubt,” said another insider familiar with her book, which she co-wrote with David Ritz and is published by Hyperion.