With Monday's release of veteran defensive end Charles Johnson and safety Kurt Coleman, general manager Marty Hurney has cleared just over $9.6 million in cap space in the past three days. The Panthers now have close to $30 million in cap space.
Stewart, who will turn 31 on March 21, was coming off one of his worst seasons statistically behind an offensive line Hurney regarded as one of the top five in the league. Stewart averaged a career-low 3.4 yards per carry (680 yards on 198 carries), and his total yards were his fewest since 2013, when he was limited by injuries.
His yards per carry ranked 32nd among the 34 running backs who had at least 150 carries last season, ahead of only Adrian Peterson and Ameer Abdullah, according to ESPN Stats & Information. Stewart's 3.55 yards per touch last season were the fewest by a running back with at least 200 touches in a season since BenJarvus Green-Ellis (3.47) and Rashard Mendenhall (3.49) in 2013.
Stewart ends his career at Carolina, where Hurney selected him in the first round of the 2008 draft, with 7,318 yards. He surpassed DeAngelo Williams last season as the team's all-time leading rusher.
Williams was released by former general manager Dave Gettleman after the 2014 season.
Stewart recently said he still could be a productive back. But with new offensive coordinator Norv Turner trying to create more opportunities for 2017 first-round pick Christian McCaffrey and what Hurney called a deep draft class at running back, the Panthers opted to move on.
Hurney added that the staff is confident McCaffrey can run more between the tackles even though he is a bit undersized at 5-foot-11 and 205 pounds.
"Norv Turner has come in and we've had several meetings with him," Hurney told ESPN on Tuesday. "We know how he wants the offense to look. Christian McCaffrey is a very versatile running back, and he can do a lot of different things. We have to continue to work through the roles that he will play as well as the roles for all the other guys on the offense."
In 2018, McCaffrey will try to end the Panthers' drought without a 1,000-yard rusher. Carolina hasn't had one since 2009, when both Williams and Stewart broke 1,000 yards. That's the longest active drought by a team in the NFL, according to ESPN Stats & Information.
While Hurney said it was too early to speculate on signing either, in describing his philosophy he immediately pointed to both interior line positions.
"You always have to be very strong on the offensive line and defensive line," Hurney said. "Our offensive line, I would think, was top five in the league last year. And our defensive line, we were able to put consistent pressure, not only outside but from the inside. That's very important these days because so many of these quarterbacks get the ball out of their hands so quickly."