Carolina Panthers head coach Ron Rivera told reporters Monday that running back Jonathan Stewart will likely miss "at least a week or two" because of a hamstring injury sustained in Sunday's win over the San Francisco 49ers.

Rivera confirmed Stewart underwent an MRI, but said the team is still waiting for the results.

Without Stewart, Rivera said that Cameron Artis-Payne will likely be the starter, with Fozzy Whittaker and Mike Tolbert acting as change-of-pace backs.

"If Jonathan's out for an extended period, we feel good about the guys we have," said Rivera.

Stewart entered Sunday with an ankle issue, and has struggled throughout his career to consistently stay healthy.

His absence could mean an even bigger workload for quarterback Cam Newton, who's a large part of Carolina's running game. The Panthers face the Minnesota Vikings and their stifling run defense in Week 3.

Fantasy Fallout: Fozzy a mediocre fill-in for Jonathan Stewart