Running back Arian Foster has always been a bit of an iconoclast among NFL players, so it makes sense that he walked away from the game in a sudden way.

A day after the Miami Dolphins beat the Buffalo Bills, not even halfway through his first season with the Dolphins, Foster announced he’s done with the NFL. He did so on Uninterrupted, a site in which athletes speak directly to the fans.

Foster, who turned 30 in August, said he walks away “with peace.” He said his body just couldn’t hold up anymore.

“I know it’s not commonplace to do it midseason, but my body just can’t take the punishment this game asks for any longer,” Foster wrote. “I want to thank the Miami Dolphins, with everything in me, for allowing me to bow out with grace and making this process as easy as possible. It means everything to my family and I. I’ve created lifelong relationships in my short time there that I’m forever thankful for.”

Foster said it was hard to step away “because this game has been everything to me … my therapy, my joy, my solace and my enemy.”

“I’ve given a lot to this game and given up a lot for it,” Foster wrote. “But it has returned to me more than I could have ever asked for. Faceless gladiators have been shuffled in and out of this arena for decades and I’m proud to have taken part in that legacy.”

After a long, fantastic run with the Houston Texans, Foster was signed this offseason by Miami and was the team’s Week 1 starter. He missed three games with a groin injury but returned to play in Miami’s last two games. On Sunday he had three carries for 5 yards, while teammate Jay Ajayi had his second straight 200-yard game.

Foster was coming back from a torn Achilles tendon that cut his 2015 season short after just four games. Foster hadn’t played all 16 games in a season since 2012.

If Foster is done with the NFL for good, he retires with 6,527 yards and 54 touchdowns. He led the NFL with 1,616 rushing yards and 16 touchdowns in 2010, and was a four-time Pro Bowler. Not bad for an undrafted back out of Tennessee.

Arian Foster suddenly announced his retirement on Monday (AP) More

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Frank Schwab is the editor of Shutdown Corner on Yahoo Sports. Have a tip? Email him at shutdown.corner@yahoo.com or follow him on Twitter!

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