O.J. Simpson said he fears for Bill Cosby’s safety in prison and, after nine years experiencing what life is like behind bars, he ought to know.

“The problem is the nature of the crime,” he said, according to TMZ. “Rapists are frowned upon in prison.”

Cosby became the first celebrity to be sentenced amid the #MeToo movement after he was convicted of three counts of aggravated indecent assault on Andrea Constand and sentenced to three to 10 years in state prison on Tuesday.

Simpson said there will likely be people protecting Cosby, but he was still not sure how safe the disgraced 81-year-old would be in prison.

“They're gonna have to put him in protective custody ... because it takes one nut, ya know?,” Simpson said, according to TMZ. “With his health and his age and the nature of the crime, there's not a warden in this country wants the responsibility of a Bill Cosby. I think they should let him do his time under house arrest.”

Simpson was released from prison last year after serving nine years for armed robbery at a Nevada facility.

While serving out his sentence, Simpson was paired with brawny cellmate Greg Lewis, who “could take care of business if anybody hassled him,” a prison guard said, according to CNN.

Following the sentencing, Cosby’s publicist Andrew Wyatt called the ordeal “the most racist and sexist trial in the history of the United States,” according to People magazine. “They persecuted Jesus and look what happened. I’m not saying Mr. Cosby’s Jesus but we know what this country has done to black men for centuries.”

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