CHARLOTTE, N.C. -- This is the first of an 11-part roster analysis of the Carolina Panthers, beginning with a position that is at the core of the offensive philosophy.

First up: Running back

The Panthers could move on from Jonathan Stewart if they choose to overhaul the running back position. Jeremy Brevard/USA TODAY Sports

2016 grade: C-plus. There’s no question catastrophic injuries to the offensive line hurt the running game, which ranked 10th in the NFL a year after being No. 2. That leading rusher Jonathan Stewart missed three games with a hamstring injury didn’t help. Neither did Carolina beginning to move away from the read-option that has been a huge part quarterback Cam Newton's success. Newton had a career-low 90 rushing attempts for a career-low 359 yards.

Under contract (2017 salary cap number): Jonathan Stewart ($8,250,000), Mike Tolbert ($1,850,000), Cameron Artis-Payne ($656,563).

Key free agents: Fozzy Whittaker, UFA

The good: Stewart showed in a December Monday night win at Washington that he can be productive, rushing 25 times for a season-best 132 yards. He ran as hard as he has all season behind a line that had only one starter who was at the same position to begin the season. His nine rushing touchdowns were as many as he had the last three years combined and his most since collecting 10 in 2009.

The bad: Stewart turns 30 in March, an age when production of running backs typically declines. Despite his effort against Washington, he has missed three games in each of the past three seasons due to injuries and has been injury-prone throughout his career. Fullback/running back Mike Tolbert, 31, was a non-factor for much of the season. A short-yardage back, he has only one rushing touchdown in the past three seasons and had none this season. Second-year back Cameron Artis-Payne was active only for the three games Stewart was out. He’s yet to show he consistently can shoulder the load as an every-down back.

The draft: The Panthers haven’t taken a running back in the first round since selecting Stewart with the 13th pick in 2008. This draft is particularly strong at running back, so it wouldn’t be a huge surprise if Carolina selected one with the No. 8 overall pick. Among the candidates that might be available are LSU’s Leonard Fournette, Florida State’s Dalvin Cook and Stanford’s Christian McCaffrey. Fresh legs, as Dallas first-round pick Ezekiel Elliott showed in leading the league in rushing this season, can be a difference-maker. The Panthers need a future replacement for Stewart who can make a difference.

Final thought: Coach Ron Rivera wants to evolve the offense so Newton won’t have to shoulder the load as a rusher in the read-option. Beyond upgrading the offensive line, finding a long-term solution at running back is key. Stewart is a short-term solution at best. With the draft deep at running back, it only makes sense to spend either a first- or second-round pick on that position. If you do that, then releasing Stewart with a post-June 1 designation to save $6.25 million under the salary cap makes sense. I could see a scenario where Carolina completely overhauls the position by not bringing back Stewart, Tolbert or Whittaker.