Running backs are becoming disposable at a younger age each year in the NFL it seems, and Michael Turner is a grandpa by league standards.

There’s a reason why the 240-pound back is still a free agent, and it isn’t because there isn’t a need on some rosters or that GMs simply don’t understand what he can do for their team — it’s because his skills have rapidly declined over the last 18 months and he doesn’t possess the abilities to be an every-game feature back anymore.

At 31 years of age, Turner is coming off of a season where he looked heavy, old and slow en route to posting career-worst numbers as a starter across the board, including a paltry 3.6 yards per carry average. Yet when the Atlanta Falcons released Turner after a failed physical in March, it was still somehow widely assumed that the “burner” would find a role somewhere else before long.

The fact that he hasn’t shouldn’t be shocking — it simply shows that NFL GMs are getting smarter.

If anyone were going to sign Turner this week, the New York Giants seemed like the team after starting RB David Wilson coughed the ball up like it was his job in the season opener. However, the Giants elected to pick up another veteran that already knows the offense in Brandon Jacobs, leaving Turner languishing and aging in free agency.

Even though Turner is no longer a feature back in the NFL, it is still feasible to see him earn a spot somewhere with a very limited role. Although his 4.49 speed that earned him his infamous nickname is a thing of the past, large veteran backs like Turner are still valuable in short yardage situations and blitz pickups. The question then becomes: would Turner be willing to accept such a role?

While it’s unknown if any teams have expressed any legitimate interest in Turner in recent weeks, if he isn’t willing to accept a specialist role, there’s a good chance that Turner may have played his last snap in the NFL.

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Will Reeve is an NFL writer for www.RantSports.com. Follow him on Twitter @WillReeveJr, “Like” him on Facebook or add him to your network on Google.