Rashard Mendenhall may be the first man ever who can say that in the span of one year he went from starting on an NFL team to writing for an HBO show.

The 26-year-old former Pittsburgh Steelers and Arizona Cardinals running back wrote in a Huffington Post blog post that since retiring from the NFL in March he has moved to Los Angeles and become a member of the Writers Guild of America, West.

Mendenhall, who was on two AFC championship teams with the Steelers and earned a Super Bowl ring in 2009, says he is working on an HBO show that will air next summer:

"A year ago, a writing career was just a tiny seed of thought as I prepared for my sixth NFL season. And as I write this now, it has already begun to sprout. Through this experience I've learned that you can will your dreams into existence."

In addition to the two Super Bowl appearances, Mendenhall made headlines during his NFL career for a questionable tweet about 9/11 and a 2012 suspension after he failed to show up for a game.

In six NFL seasons, Mendenhall rushed for 37 touchdowns and 4,236 yards. He was the Steelers' first-round pick in 2008. His best season was 2012 when he ran for 1,273 yards and 13 touchdowns.

When he retired in March he wrote, "The truth is, I don't really think my walking away is that big of deal. For me it's saying, 'Football was pretty cool, but I don't want to play anymore. I want to travel the world and write!'"

Shortly after his Huffington Post article about his HBO show was published, Mendenhall sent out this tweet:

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