SBW to release tell-all autobiography with help from Once Were Warriors author Alan Duff

For the first time ever, Sonny Bill Williams is telling his story.

Sonny Bill Williams. Source: Photosport

The rugby and league superstar has enlisted the services of Once Were Warriors author Alan Duff to create his tell-all autobiography set for release later this year.

The former All Black and Kiwi sensation will delve into the highs and lows of a career which has taken him across the globe, as well as his personal life.

"Telling my story is not something that is easy for me," Williams said.

"But I know there are young kids who are growing up dreaming of a different life to the one they are living every day.

"Dreaming of being the best they can be in sport or conquering the world in other ways.

"And so, sharing my story, the good and bad of it, is to help them and to inspire others."

Duff, renowned for the success of his debut novel Once Were Warriors, said he was "honoured" to be working with Williams.

"He is not only the definition of number one in sports, but, of more importance, a good and humble man."

The autobiography has been set for release on September 29.