Could Tolbert's signing affect AFC North?

Chargers free-agent running back Mike Tolbert signed a four-year contract with the Carolina Panthers, a source told AFC West blogger Bill Williamson.

That ends the speculation that the Pittsburgh Steelers were in the mix for Tolbert. In fact, the Pittsburgh Post-Gazette is reporting that the Steelers were never interested and never contacted Tolbert or his agent.

But the addition of Tolbert could lead to the Panthers shopping Jonathan Stewart as part of a trade, according to NFC South blogger Pat Yasinskas. Stewart is entering the final year of his rookie contract and will earn $1.3 million.

Could Stewart interest anyone in the AFC North? Every team in the division needs a running back in some capacity, and every team should look hard at Stewart. The Bengals, Browns and Steelers all will have different starting running backs than last year, and the Ravens could use a backup for Ray Rice (although it looks like they will go with Anthony Allen at first).

No one knows whether Stewart will come available, but someone in the AFC North should show interest in him. Stewart is young (24), productive (averaged 4.8 yards per carry in his four-year NFL career) and versatile (two seasons of 1,000 total yards). He'll give you more than Michael Bush, BenJarvus Green-Ellis or other free-agent running backs, but Stewart is going to cost a draft pick (perhaps a third-rounder).

The biggest concern when looking at veteran running backs is their wear-and-tear, but Stewart has very little because he's been teamed with DeAngelo Williams. Stewart has never carried the ball more than 221 times in a season and has ran it less than 200 times in each of the past two years.

Let's see if speculation turns into something more substantial this time.