CHARLOTTE, N.C. (AP) The Carolina Panthers might have to rely on Fozzy Whittaker and Cameron Artis-Payne to carry their running game for a while.
Panthers coach Ron Rivera expressed concern over Jonathan Stewart's injured hamstring that forced the nine-year pro to leave Carolina's 47-26 win Sunday over the San Francisco 49ers in the first quarter.
Whittaker filled in nicely, carrying 16 times for a career-high 100 yards , although he did fumble once. Whittaker, who came into the league as an undrafted rookie in 2012 with the Arizona Cardinals, also had three receptions for 31 yards.
''Fozzy picked up the rifle and kept shooting,'' quarterback Cam Newton said.
The Panthers racked up 529 yards and 26 first downs.
If Stewart is out, Whittaker would start next Sunday against the Minnesota Vikings and Artis-Payne will likely see his first action in a backup role. Artis-Payne has been deactivated the first two games.
Fullback Mike Tolbert, who had nine carries for 25 yards, could see additional carries, too.
''I thought (Whittaker) and Mike Tolbert mixed it up well,'' Panthers coach Ron Rivera said. ''When you have backs with that kind of ability, it's good. If Jonathan's (absence) is prolonged, then we certainly will get an opportunity to see Cameron Artis-Payne out there, which I'm pretty excited about, because he is a heck of a young football player.''
Things we learned from the 49ers-Panthers:
49ERS DEFENSE: Holding Case Keenum's offense in check against the Rams is one thing. Keeping up with Newton and Kelvin Benjamin proved to be something else altogether for the 49ers defense. It went from pitching a shutout to allowing 39 points (seven of Carolina's points came on a defensive touchdown).
Next up: Seattle, which struggled to put up 12 points in a Week 1 win against Miami, but whose defense routinely puts points on the scoreboard.
''(The defense is) more confident, more comfortable,'' said 49ers linebacker NaVorro Bowman, who had four tackles. ''It's the second game, and having the chance to win on the road against the Carolina Panthers, we can do nothing but go up.''
GABBERT'S DAY: At 6-foot-4 and 235 pounds, 49ers quarterback Blaine Gabbert gives away just an inch and 10 pounds to Newton. Gabbert also topped Newton 1-0 in rushing touchdowns and managed 243 yards passing, but had two interceptions late in the game. Gabbert took shots at Carolina's young cornerbacks, but will face an experienced secondary against Seattle next week.
''When you get one-on-one on the outside, and they're playing their corners in single coverage, you have to take your shots,'' said Gabbert, who completed passes of 75, 28 and 20 yards against Carolina. ''You're not going to get every one of them, but you have to put the thought in their defense's mind that you're going to take shots 100 percent when you get them.''
HYDE STRUGGLES: After a two-touchdown performance in an opening-week win against Los Angeles, 49ers running back Carlos Hyde didn't factor into a 46-27 loss to Carolina on Sunday. The Panthers held him to 34 yards, with no run longer than 8 yards. They also forced a fumble by Hyde that resulted in Shaw Thompson's scoop-and-score touchdown.
''I came off a good week and then performed this way, and it's just unacceptable,'' said Hyde, who rushed for 88 yards in Week 1. ''Coach will be calling my number, and I'm the guy who's going to help win games for this team. I need to put our team in position to win, and today, I didn't do that.''
TIGHT ENDS A FACTOR: Gabbert and Newton each connected for two passes of more than 50 yards on Sunday. Two of those long strikes went to tight ends - Greg Olsen (78 yards) for Carolina, and Vance McDonald (75) for San Francisco. Both went for scores, and both were career longs.
It marked the first game in NFL history in which a tight end on each team had a touchdown catch of at least 75 yards.
McDonald, though, rued a dropped pass on a similar route while the 49ers mounted an unlikely comeback in the fourth quarter that might have changed the outcome.
''I felt like running a 400-meter dash,'' said McDonald, who will face another defense with top-notch linebackers against the Seahawks in Week 2. ''The next one (the drop) is the one that hurts and the one that matters.''
GROWING PAINS: Panthers rookie cornerbacks James Bradberry gave up one touchdown, but also came up with an interception on Gabbert. Carolina knows there will be growing pains with Bradberry and fellow rookie Daryl Worley, who was beat on two occasions, but Rivera is confident both have what it takes to be successful moving forward.
AP freelance writer Eli Pacheco contributed to this report.
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