Evaluating running backs has become a tricky business in recent years.
It wasn't long ago that everybody was looking for the new Walter Payton—a complete running back that could carry the load while also being trusted to catch passes, block like a fullback and protect the quarterback—but that isn't the case anymore.
There are no longer many true every-down runners, and fewer still season-long workhorses that will see the kind of workload past greats received.
For evidence of this, look at Emmitt Smith, who averaged 324 carries per season for his first 10 years. That is more than any other running back last season outside of Maurice Jones-Drew, who was forced into so many carries as much by the quarterback situation in Jacksonville as anything else.
Only one other runner had more than 300 carries last season (Atlanta's Michael Turner with 301), and the recent talk has been of how his workload needs to be shared with Jacquizz Rodgers.
The days of the do-everything running back are fading, so what we are now looking at is a league full of specialists, each of whom has carved out their own special niche in an offense.
When analyzing running backs today, you aren't simply looking at a checklist of skills to see if that player can be a total player. You're looking at the skills he has and trying to project those skills into offenses in the NFL to see how that player could be used by particular teams.
One team's trash becomes another team's treasure, because they are better prepared to make use of that player's unique skill set.
We're going to look at certain traits and how they have helped some players succeed in particular situations.