A year removed from leaving professional football in his prime, Rashard Mendenhall is happy being out of the NFL. He's also happy to share some of his experiences, including what he saw of the player culture in the NFL.

In a feature published by Men's Journal, Mendenhall has plenty of juicy bits of info and insight. But one stands out, particularly as the topic of hazing and bullying remain relevant to the NFL.

The former running back says that, while a member of the Pittsburgh Steelers, rookie hazing involved forcing the newbies to pay for big parties and nights out on the town. On one occasion, a group of men that included star quarterback Ben Roethlisberger were out on the town.

A rookie offensive lineman was asked to give his credit card to Roethlisberger, which he did.

The quarterback then turned around and used the card to cover the group's tab at the club -- a figure that hit $25,000.

Those experiences are proving valuable to Mendenhall now. After retiring at 26 last offseason, Mendenhall said he wanted to pursue creative interests, which included writing.

He had no idea what was coming around the corner: HBO offered the ex-running back a three-week contract to write for an upcoming drama, "Ballers." Mendenhall took the offer, assuming that three-week stint would be the end of it.

"Coming from football, you know you can get cut at any moment," he tells Men's Journal.

Mendenhall started out consulting on the accuracy of the scripts, lending an authenticity to how the show portrayed the lifestyles of rich, young millionaires and the ways they interacted with themselves.

Mendenhall was eventually signed on for the rest of the first season, which debuted on HBO last month.

The show's biggest name is Dwayne 'The Rock' Johnson, who plays a football player who isn't sure when to retire -- and who is starting to feel the effects of a career spent taking hits to the head. Mendenhall was a key contributor to the development of that character.

"Rashard just had a different point of view than other players we talked to," says one of the show's executive producers to Men's Journal. "He's so thoughtful and introspective and curious, and he's got real creativity."

Mendenhall has moved from Chicago out to Santa Monica to be closer to the industry he has now joined. But being involved in a TV drama about football hasn't inspired any itch to get back out on the field.

Says Mendenhall: "Not for a second did I feel like I wanted to be back out there. I already lived that. It was complete for me. The tough part is trying to wrap my head around where I'm at now."

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