They won't say this on the record, but NFL teams want to underpay someone to overperform. That's not exactly unfair, the issue is the revolving definition of "perform" in the league and the value that gets associated with it.
Green Bay Packers running back James Starks has been an above-average running back on a pass-first team since entering the league as a sixth-round pick in 2010. Incidentally, he was the Packers leading rusher (52 yards on 11 carries) in Super Bowl XLV, capping off an impressive post-season run of 315 yards on 81 carries. He only had 21 regular season carries before being the team's featured back during the playoffs.
A player cannot show his worth better than being a late draft pick, getting called into action 13 games into the season, then running well in four playoff games and helping win a Super Bowl.
Granted, that was a while ago, but Starks has performed well for the Packers in a starting and back-up role over the last three years. The problem is, when Aaron Rodgers is your quarterback, you throw the football.
The Steelers look to throw the ball plenty with quarterback Ben Roethlisberger, but Roethlisberger and Rodgers will tell you plenty about the value of a solid running running game complimenting their throwing.
On top of that, it's an injury-prone position that is slipping in value. Houston's Ben Tate, another sub who's performed well when given an opportunity signed a 2-year, $7 million deal with the Cleveland Browns Saturday - four days after free agency opened and for a total dollar amount that equates to a moderate player. Cleveland has even less running back depth than the Steelers do and they had a glut of salary cap space.
If that's all Tate could get after four days of pursuing a new job, Starks will come at or right around league minimum, and he's a player who could end up seeing a fair amount of playing time, given the Steelers' varied offense and the amount of touches Le'Veon Bell has already had in his 13 games with the Steelers.
Built similarly to Bell but without the same kind of receiving skills, he could be an excellent counterpart of what could be a formidable ground game in the future.