Phil Jackson Phil Jackson

Former Los Angeles Lakers coach Phil Jackson reveals in his new book Eleven Rings that he was diagnosed with prostate cancer in 2011, according to the Orange County Register.

In the memoir, Jackson says he revealed his diagnosis to the team during the 2011 conference semifinals against the Dallas Mavericks as a way to motivate his players. Jackson reportedly postponed undergoing surgery until after the season.

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"Shocking," Lakers' forward-center Pau Gasol told the newspaper. "But then you also could understand certain moments of his demeanor, energy and involvement because of what he was going through health-wise. It explained certain things. It was a shock. A difficult moment for the team."

Jackson, 67, retired as the Lakers coach after that season. Eleven Rings hits stores on May 21.