Running back Rashard Mendenhall doesn't fit the stereotype of a "regular" NFL player.

At one point early in the offseason, Ryan Williams looked over at teammate Rashard Mendenhall sitting at his nearby locker and reading a book.

Williams couldn't recall the name of the book, but he remembered it was about Native Americans and how they were poorly treated in the early days of the United States.

"I knew then his mind was on a whole other level," Williams said of his fellow running back. "You could have a conversation and he'd probably beat you up mentally with the things he knows."

Mendenhall was signed to a one-year deal in March in order to give the Cardinals a lift at the backfield position. His rookie contract over with the Steelers, Mendenhall had been a workhorse back under Cardinals coach Bruce Arians when Arians was the offensive coordinator in Pittsburgh. He tore his ACL at the end of the 2011 season, derailing his time with the Steelers and all but wiping out production in 2012.

Mendenhall arrived in Arizona bringing with him more than just a pair of 1,000-yard seasons (and likely a third without his injury), however. He is a smart, thoughtful man who admittedly isn't going to fit neatly into the box of typical football player.

Had he not been playing in the NFL, he figures he would be writing even more of the poetry that

takes up a chunk of his time, or trying to get a book published. Perhaps he'd be working in a bookstore.

Mendenhall understands why many don't see the parallels between his other interests and his day job. Maybe, though, they should look through his prism.

"They don't because of stereotypes of how they see football," Mendenhall said. "But actually, it fits perfectly as far as what I do in the backfield. I think it's all creative, feeling the defense move. It's poetry in its own right. It's creative in its own right."

Growing up, Mendenhall 's mother emphasized to Rashard and his siblings the importance of education. She put them in different schools, different classes. She made sure there was always a book being read. The arts beckoned Mendenhall early, including music and drawing.

Eventually, though, he gravitated most to writing, writing a lot of poetry and now, posting occasionally on a blog set up for him on huffingtonpost.com.

Sometimes he touches on football. Mostly, he does not.

"Every part of us as individuals is us, so I'm proud of every part of me," Mendenhall said. "I'm proud of what I have done in football. I'm proud with how I've grown and learned."

Only 26, Mendenhall admitted sometimes people see him as an "old soul." He definitely has strong opinions and sometimes, he shares them.

At one point in 2011, he tweeted about 9/11, drawing a firestorm of criticism. Mendenhall said at the time he was just trying to get people to think, and now, he said he has distanced himself from anything in the past. Moving forward is the only option, he said, in football and in life.

He couldn't have come to a better spot. Arians was the one running the show when Mendenhall had his best seasons, and many believe Arians is the one coach who can truly draw the best out of a different personality.

"I love him as a person," Arians said. "He thinks outside the box. He's not your normal NFL guy as far as the way he thinks and I really appreciate that. That shows his inner strength to me.

"I have all the respect for him as a talented football player but I have even more respect for him off the football field because he can stay who he is and doesn't conform."

Mendenhall loves the idea Arians is blunt and honest, saying the two have a "great relationship." He's also building a relationship with his running back mates.

"One of the things I loved about him, even before he got to this locker room, he's not afraid to speak his mind," Williams said. "People don't do that because of how society will think of them and I already knew he wouldn't have a problem with that. He's going to be him until the day he's six feet deep. I can respect that.

"If you haven't sat down with (jersey No.) 28 and had a chance to get to know him … you would never know what kind of person he is," Williams said. "He's a good dude."

Mendenhall described himself in a good place in his life. Most of his writing has never been seen in public. That will come someday, but now is the time for his first job. He is anxious to show his knee injury is behind him and that he is worth a contract extension beyond 2013. The sport does mean something to him, despite the way he views life.

Life, though, isn't just football. One of Mendenhall's poems (which can be seen here) echoes those thoughts.

A King, not a servant, even if I'm crownless

In this world you're limited by the views of those around you

But I don't live by this world's standards

And that's why I'm boundless