EXCLUSIVE: Sugar Ray Leonard on Past Substance Abuse: I Would Wake Up and Not Remember What Happened

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Behind his clean-cut appearance and classy reputation, Sugar Ray Leonard was fighting demons that few knew about.

The International Boxing Hall of Famer opens up about his drug-addled past and the strain it placed on his relationships on Oprah: Where Are They Now?, and ET has an exclusive clip.

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"There was a part of me that's Ray Leonard -- that's a good man, that's an honest man -- and then there's Sugar Ray Leonard, who is ego-driven, who is a tough S.O.B. in the ring, who had money, who had fame and at some point didn't really appreciate it and took advantage of that," Leonard says.

During his prime in the 1980s, Leonard won world titles in multiple weight divisions and was named "Boxer of the Decade," but behind the accolades, one of the world's greatest athletes was troubled by substance abuse, infidelity and the emotional damage from a childhood molestation, as detailed in his 2011 memoir, The Big Fight: My Life In and Out of the Ring.

"My first wife, Juanita, she always said, 'You're two different people,'" Leonard continues. "I used to get angry about that and go have a drink. Then when my present wife, Bernadette, said to me, 'There are two of you,' I knew there was a problem."

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Leonard reveals there were many days when he would wake up in the morning unable to recall what had taken place the night before.

"I always knew I had a problem," he says. "I just never admitted it to myself."

Leonard is proud to announce that he has been clean and sober since July 4, 2006.

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"Nine years ago I woke up, and life couldn't be better," he says.

Oprah: Where Are They Now? airs Saturdays at 10 p.m. ET/PT on OWN: Oprah Winfrey Network.