The running back position has been devalued over the years. Teams are going with a group rather than a feature back. Front offices are reluctant to use money or a high draft pick on a premier back. And now because of injuries and age, the position is as weak as it ever has been.

Adrian Peterson and Jamaal Charles are coming off ACL injuries.

Ryan Mathews suffered a broken clavicle on his first preseason carry. And Darren McFadden played seven games last year and has never played more than 13 in a season in his four-year career.

The dreaded 30-year-old mark is approaching for some of the league's top backs, too. Four of the 15 1,000-yard backs from 2011 are 29 years old or older -- Frank Gore, Willis McGahee, Steven Jackson and Cedric Benson.

Then there's Chris Johnson, who is three years removed from becoming the sixth player to rush for 2,000 yards but had career lows in rushing yards (1,047), yards per carry (4.0) and touchdowns (four) in 2011 despite playing in all 16 games.

Who is even considered the best back in the league?

Arian Foster has put together consecutive impressive seasons. Maurice Jones-Drew led the league in rushing with 1,606 yards in 2011. Ray Rice is the key to the Ravens' success. And LeSean McCoy shows flashes of Barry Sanders at times.

The league has plenty of capable backs but far more questions surrounding the position in 2012.

- Jeffrey Tomik