CHARLOTTE, N.C. -- Jonathan Stewart always sprints to the end zone when he finishes the "H" drill that tests many of the skills necessary to be a great all-around running back.

It's a routine he began in 2008 when the Carolina Panthers selected him with the 13th pick of the NFL draft. He did it then because that's what DeAngelo Williams, a first-round pick in 2006, did.

He still does it even tough Williams now is a member of the Pittsburgh Steelers, who play the Panthers in Thursday night's preseason finale.

Few would have imagined a few years ago that Stewart still would be running this drill, much less chasing Williams as Carolina's all-time leading rusher, because of the injuries.

Now it seems like only a matter of time before Stewart will get the 1,033 yards needed to surpass his old friend and teammate, who rushed for 6,846 yards from 2006-2014.

"It would mean a lot," Stewart admitted. "It's definitely something that says a lot about your career, but my ultimate goal is to get back to the Super Bowl."

Stewart wasn't a factor in Super Bowl 50. He injured his foot on Carolina's fifth offensive play. He returned, but finished with only 29 yards on 12 carries.

But Stewart is far from finished. One could argue he's at the peak of his career, better than he was in 2009 when he and Williams became the first pair of backs from one team to top 1,100 yards rushing.

That's when the duo became known as "Double Trouble."

Stewart had 1,133 that season. He was on a pace to eclipse that a year ago before a minor knee injury forced him to miss the final three regular-season games. He still had 989 yards rushing, and added another 218 in three playoff games.

"That's why we stuck with him," Carolina coach Ron Rivera said. "That's why we done the things we've done to put him in the position to be our featured back now."

Stewart doesn't consistently get the credit Williams did when he was the lead back. But the Panthers believed in Stewart enough after the 2014 season that they let Williams go, a move that wasn't popular with many fans at the time.

"He's the type of guy everyone needs on their team," running backs coach Jim Skipper said.

Stewart is unselfish. He doesn't have a huge ego like a lot of backs. He's more worried about wins than his carries.

He's also soft-spoken, maybe more than anybody on Carolina's roster. Listening to him tickle the ivory as he plays the piano by ear you'd never guess he made a living running over -- some sometimes through -- people.

But when Stewart puts the pads on he becomes one of the more valuable members of an offense that led the NFL in scoring last season. Not quite as valuable as quarterback Cam Newton, but again more than he gets credit.

"The guy has a low-key demeanor, and on game day he takes it up another notch," Skipper said.

That's Stewart's competitive nature, the thing that drove him to overcome the ankle injuries that three years ago made him a risk in any fantasy football draft.

"He's a tremendous competitor," Skipper said. "Those are things you can't measure on an individual, he has it. He's fought through all of those dinks and bruises and he just kept on hammering."

Rivera says Stewart has grown up "a lot as a football player" since Williams was released. Stewart also has shown that he can be more than the second half of a one-two punch.

He can be the lead jab.

He also can line up inside or outside as a receiver and help protect Newton on a blitz.

"Mentally, there's a lot on the table, more than the average eyes sees," Skipper said. "And Stew does all those things."

But what Stewart does that few outside of his coaches and teammates see -- and on a daily basis -- is run to the end zone at the end of "H" drill.

"It's good to see," Rivera said. "I don't think people give him the credit for how hard he works and how good he is."