Mike Tyson says it was his own battle with addiction and depression that led him to knowing the late Robin Williams.
During his interview on Howard Stern's SiriusXM radio show on Wednesday, the 48-year-old boxer revealed that he and the actor attended meetings together designed to help them cope with their demons. "People that deal with this situation (addiction), we know each other," Tyson explained.
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Tyson also recalled a time when Williams confronted him about where he was getting his drugs. "This is very interesting," he began. "When I met him and he said, 'I was waiting for you.' ...He started telling me about somebody I was purchasing from. I said to myself, 'How does he know this lowlife dealer I know? They shouldn't be in the same state.' You go to every measure to get high. Everybody knows everybody."
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The heavyweight champion admitted that the Oscar winner's death this past September threw him. "It's scary. ...If you have a mental illness, you're going to think about suicide. Suicide is our comfort."
When asked to elaborate on what it feels like to struggle with something like drug addiction, Tyson explained, "Think of it like this. Think about you're starving, you're absolutely famished. And that drug -- heroin, cocaine -- that's food."
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As of late, the heavyweight champion is off the drugs, but tells Stern, "I'm clean now, but this is a constant fight. Eventually that dark entity's going to knock on the door."
He added, "The fact is we're all human and it doesn't care what race you are, how rich you are, it just wants you to be miserable."
On Sunday night, Williams' kids paid tribute to their father -- a huge San Francisco Giants fan -- by throwing out the first pitch at Game 5 of the World Series. Check out the heartfelt moment, below: