And the 28-year-old is anxious to make the most of the opportunity.
When Carolina released its all-time leading rusher DeAngelo Williams in March in a salary cap move, it paved the way for Stewart to step in and become the team's No. 1 back. The 5-foot-10, 228-pounder who combines shiftiness and power says it won't change his approach.
Stewart said he's always prepared as though he's going to start.
''So in all reality, nothing is really different going into the season,'' Stewart said.
Except that Carolina's 1-2 punch of former first-round draft picks is gone.
When healthy, Williams has been the starter in Carolina for most the last seven years, although the Panthers have viewed it as a split-carry backfield.
Stewart has played in 90 career games, starting just 28 - most of those coming when Williams was unable to play. He's managed to put up big numbers at times, twice rushing for 10 touchdowns in a season and once piling up 1,133 yards in 2009.
His strong finish last season helped convince the Panthers he still has what it takes to be the premier ball carrier following injury-plagued seasons in 2012 and 2013 that kept him out of 17 games. Stewart ran for 486 yards and averaged 5.3 yards per carry in Carolina's final five games in 2014 after Williams got hurt.
Tight end Greg Olsen studied those games on tape this offseason and believes Stewart is one of the most underrated backs in the league.
''We saw last year that as he got more and more reps, the better he got,'' Olsen said. ''He's so talented. You forget that he's just unbelievable. When he gets rolling he's as good as there is in the league. He's so big and strong.''
Stewart, an accomplished pianist, isn't the type to gripe about not getting more carries or not starting.
It's not in his makeup.
Quiet and relatively shy, Stewart has always put the team before his personal goals, never once complaining publicly about being Williams' backup.
But now it's his time to shine - and he's intrigued by the idea of getting more touches in a game.
''It's all about rhythm and the more you run, the more you do something, the more comfortable you are and able to gauge things,'' Stewart said. ''It's like when you get in a car. The more you drive from one route to another, the more comfortable you get.''
Panthers coach Ron Rivera was non-committal as to how many times he'd like Stewart to carry the football during a game, adding that he's encouraged by what he's seen in OTAs from young backs Fozzy Whittaker and Cam Artis-Payne.
''Honestly it's going to come down to how you are doing,'' Rivera said. ''If you are running the ball well, obviously you are going to feed him. We would like to be able to run the ball when we have to and run the ball when we want to.''
Rivera adds that ''hopefully'' Stewart can stay healthy.
Looking to add strength and flexibility, Stewart turned to yoga last offseason and liked the results. He played in 13 games last season with a career-high eight starts, rushing for 809 yards and three TDs.
''I feel like it does something for me,'' Stewart said of the yoga routine, adding that he feels stronger and more sure-footed than he has in years.
The Panthers are hoping Stewart can emerge from Williams' shadows and win the NFC South for a record third straight season.
Stewart, who was nearly inseparable with Williams during his tenure in Carolina, still misses his old friend.
Williams has since signed with the Pittsburgh Steelers, but the two still keep in touch.
''You always think about the things that you are used to,'' Stewart said. ''Walking in and seeing someone else in the locker next to you is different. But as time goes on it's like anything else, you adjust to it.''
NOTES: Rivera said that wide receiver Kelvin Benjamin could return to practice Tuesday after missing all of OTAs with a strained hamstring.
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