Mark Schultz is one of the most decorated wrestlers in U.S. history. So was his brother, Dave Schultz. As Olympians in need of funding for their rigorous training regimens, Mark and Dave connected with a man named John du Pont, a multi-millionaire obsessed with building an elite wrestling team.

Mark was an assistant coach at Villanova when he first became involved with du Pont, who sponsored the university's team with the wealth from his family fortune. After the school dropped the sport, Mark stuck with du Pont as a member of Team Foxcatcher, a club of wrestlers named after du Pont's sprawling estate in Pennsylvania.

It was on that estate that du Pont fatally shot Dave Schultz three times on January 26, 1996. After a 48-hour standoff with police, du Pont was arrested. He was convicted of third-degree murder and died in prison in 2010.

Mark's side of that tragic story is chronicled in his new book, Foxcatcher. A film adaptation, which stars Channing Tatum, Mark Ruffalo and Steve Carell, opens in theaters Friday. In an extended interview with ThePostGame, Mark discussed his unsettling relationship with du Pont, his reflections on his brother's murder 18 years later, and du Pont's grizzly secret Mark kept in confidence -- until now.

"A lot of people don't know this about du Pont, but he was actually a eunuch," Schultz says. "I think it explains a lot about his personality. He had to take artificial testosterone supplements. He was thrown onto a fence by a horse and hurt his testicles, and then they got infected and he lost them.

"When he told me that, I genuinely felt pity for him. I haven't told many people that. He told me that in confidence. But he's dead now, so I guess it's OK."

Schultz estimates that du Pont was in his early 30s when that happened.

TPG: Did he have any romantic relationships?
SCHULTZ: Not at all. He didn't have any romance in his life. There was one girl who used to hang around. She was an Asian woman, and I think she looked at du Pont as a kind of sugar daddy who was going to help her get into acting. She was the only person I ever saw around du Pont.

[Before that] he was married to a woman for about eight months. A nurse. It was a real abuse relationship: He told me he pushed her into a fireplace once. But I think he was in love with Valentin Jordanov, the wrestler who ended up inheriting most of his estate. Dave was killed on Valentin's birthday.

TPG: What do you think attracted him to Valentin?
SCHULTZ. Lots of things. Dave was the only one who could speak to Valentin in Russian. Dave showed up to a party one time in a Bulgarian soldier's uniform, [Note: Jordanov is a Bulgarian native] and du Pont started yelling at him and telling him to take it off, saying that it was an insult, that only a Bulgarian could wear the uniform.

Du Pont would say that his mom had sex with a Bulgarian, that he was part-Bulgarian. He wanted so badly to identify with Bulgarians, maybe because of Valentin. Valentin was the only one who could stand being around him! I told him when he joined Team Foxcatcher that if he wants to stick around and make money, never learn English. If he knew English, du Pont would talk his ear off, because he did that to all of us, and it was unbearable.

Sure enough, Valentin never spoke English, and he was the only one who could stand being around him. I think du Pont became infatuated with him.

Valentin doesn't celebrate his birthday anymore, after what happened on that day.

***

Team Foxcatcher wasn't just a millionaire's hobby -- although du Pont did treat it as such. It was also the most successful team in American wrestling history. This made associations with du Pont harder for Mark and Dave to resist.

"He wasn't really a philanthropist, he would only give to get," Schultz says. "He didn't give for charity, he would give for what he wanted, which was a name of recognition. I don't know if this was true, that he got a doctorate degree in something. I never knew about that."

Du Pont received a doctorate in natural science from Villanova.

"I knew he was into biology science and I have respect for biology scientists," Schultz says. "We actually shared an interest in science."

But the two brothers did not control their wrestling fates. Money had given du Pont rare power in the wrestling world -- his riches were unprecedented, and he was willing to spend at any cost if it served his interests of vanity and notoriety.

Du Pont's eccentricities and downward spiral were well documented in news reports and subsequent books chronicling the madness at Foxcatcher Farms. But Mark Schultz's memoir is the first time that the full story is being told from his own perspective.

TPG: Foxcatcher is your own personal account of how your brother, Dave, was eventually murdered by John du Pont. It isn't the first book to chronicle this story. Why did you feel your perspective needed to be told?
SCHULTZ: None of the other books were any good. I read them. I'm speaking in the first person. This is my story. I'm not saying what other people said, I'm telling you what happened. From my perspective. I'm not, like, a reporter who's researching other people. I'm the guy that it happened to.

TPG: The first time you met du Pont, you were skeptical of him. You wound up working for him anyway. What did du Pont want? Where did this drive to run a wrestling program come from?
SCHULTZ: There were many, many motivations. I can give you several. That probably wouldn't cover all of them.

Number one, I think when he became involved in wrestling through me, he realized what the wrestling community was all about. It was kind of like a family. I think that was what he had always been missing in his life. He was a desperately lonely, sad person. He wanted to be included and respected by a group of people that were the most highly respected people on earth. Unfortunately, you can't buy your way into that, you have to earn it.

Wrestling is also a sport of close physical contact. When you wrestle, it's with the intention to cause physical pain. He had no physical contact in his life, and I think he looked to wrestling as a form of contact. He was taking the sport and perverting it, in a way, which I really resented. I think he wanted the greatest, toughest guys on earth to say good things about him, to project an image. He wanted us to say great stuff about him, to use us to promote himself. He commissioned documentaries about that stuff.

But he would take the birthday cards he made us write to him, [where we] said he was the greatest and we loved him, and he would use that stuff against you in court if you turned on him. I never saw that coming.

TPG: When du Pont first became involved with amateur wrestling, you had a sense that a multi-millionaire's interest in wrestling would be a boon for the sport. Now, of course, you know better. How did you convince yourself to keep working for du Pont even when you started to realize he wasn't stable?
SCHULTZ: We were desperate. USA Wrestling did not support us, and I had gotten fired from my job at Stanford. In fact, the year I became the best wrestler in the world, the exact day I got back from the world championships, I got fired that day. I was told it was because they couldn't afford me. They could, but they took my money and gave it to my brother [who was also coaching at Stanford].

Stability is the number one thing you need to be successful in anything. I constantly had the rug pulled out from under me. I think people were jealous of me. I think people saw me as this guy who could conquer the world.

I was fired twice. Du Pont fired me once, too. I was fired from Villanova and I never went back. I never cared. All I cared about were the Olympics, and I needed a stable training environment.

Du Pont gave me that environment at Foxcatcher. But he was always threatening to de-stabilize my training environment. I didn't have options. Title IX had wiped out wrestling programs across the country; coaches were clinging to jobs with their fingernails.

Du Pont knew I needed stability, but he wanted something in return. If you want to win, you have to associate with winners -- he knew that, to improve yourself as an athlete and as a person, you do it by associating with winners. The problem is, the people he was associating with are negatively impacted by his association, because he's a loser.

***

In the immediate aftermath of Dave Schultz's murder, many people involved tried to make sense of what happened. Mark reports in his book that if police hadn't called him and told him to stay away, he would have driven to Foxcatcher Farms and murdered du Pont himself.

In the ensuing court case, a motive for Dave's murder could not be established. Du Pont's defense argued that he was insane, but du Pont was diagnosed with paranoid schizophrenia, and it was successfully argued that he was not aware of his actions at the time he shot Dave.

TPG: I'm sure you never anticipated that even at his most extreme, du Pont would do something so drastic as commit murder.
SCHULTZ: I think if he didn't have the wealth that he had, I would have been more worried. But because he was so rich, I thought it was OK. I didn't think he was insane. But he was taking a lot of cocaine, a lot of alcohol, and I think he was a clinically paranoid schizophrenic. I think drug use was a lot of what caused some of his problems.

He did a lot of alcohol and cocaine ... but he was the only guy in the country who was willing to pay for us [wrestlers] to compete. The problem was, he had all of these conditions attached. My ideal situation was, I write Team Foxcatcher down as my team at competitions, and he would pay me. I didn't want to be around him, talk to him, be mentored by him, have him as a father figure, nothing. I just needed money. I needed to survive. I was trying to beat these Russian wrestlers that were being taken care of and paid.

U.S. amateur wrestlers were in poverty, and du Pont saw an opportunity. It was a perfect storm: These guys are poor destitute, they need financing. USA Wrestling wasn't helping us, so du Pont did.

And du Pont just dominated wrestling in this country. His teams won the national championships every single year they competed. Nobody could compete with a guy who was paying everyone to be on his team.

The problem was you had to lie for him.

TPG: How so?
SCHULTZ: Du Pont was so weak, he couldn't defend himself against anybody. That's why he carried a gun around. It was like Richie Rich, all grown up and hooked on drugs. That is exactly what Du Pont was like.

At one point I actually thought he cared about me, but it was a weird feeling, like there might have been something sexual to it.

TPG: What do you mean?
SCHULTZ: I told him this story one time about my very first match at Oklahoma. It was against Don Shuler. I was beating him 4-0, and this was the only match I never won at home. He reversed my hand, and he had my hand pinned down against his groin. His testicles were in my hand, so I just squeezed my hand and he popped off like a champagne cork. I only gave up two points instead of four and I tied him.

When I told Du Pont that story, his eyes lit up, like "Oh, you mean it's acceptable to grab someone's balls?" No, it's not. It's a one-time thing that happened. And then he invented this move called the 'Foxcatcher Five.' I almost named my book after this. Basically, it was just him grabbing someone's balls. One time, he came up to me and was like "Here comes the Foxcatcher Five" and I looked at him like, "You touch me and you're dead."

***

A film bearing the same name as the memoir opened in theaters Friday. The movie's narrative is based heavily on Schultz's memoir. Schultz was present for the movie's production and was available as a resource, particularly for Channing Tatum, who plays Mark in the movie, and for Mark Ruffalo, who portrays Dave.

TPG: What was it like being on set for the film adaptation?
SCHULTZ: When we were filming, it was not fun. The set was real quiet. It was dark. Channing Tatum's wife [Jenna Dewan] came on the set and was supposed to stay for a week. [Note: Tatum portrays Mark in the movie adaptation.] She only stayed three days. It was that unpleasant.

Mark Ruffalo [who plays Dave in the film] had never been involved in anything like this. Steve Carell, he was so different, so uncomfortable to be around, the way he looked like du Pont, and he wasn't talking very much, he wasn't pleasant. Ruffalo and Steve were in an elevator one time, and in that brief moment Steve asked Mark, "Do you think this [movie] is going to work?" and Mark said, "Honestly, I don't know."

Everything felt so real. It was very quiet, very intense. Mark and Channing went into wrestling training for seven months prior, and they got the hell beat out of them. Channing busted his head open on a mirror, busted his eardrum when Mark slapped him.

I honestly think it's going to go down as a great film. It's going to go down in history. These guys were so intense and so good. Mark Ruffalo in particular. It's hard for me to judge myself and Channing, but I knew Dave better than anyone, and I just can't imagine anyone duplicating Dave -- the way he talked, the way he moved -- the way Mark did. Mark Ruffalo was just amazing. Steve Carell had the most startling transformation.

TPG: Are you happy with how it portrays your story?
SCHULTZ: I've seen the movie three times and I've cried every time. You can't fit my entire life, even a section of my life, into two hours. You have to compress time. But in my opinion it's one of the greatest movies ever made.

-- Foxcatcher, by Mark Schultz and Dave Thomas is published by Dutton Books. It is available for purchase from the publisher, Amazon, Barnes & Noble and iTunes.

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