Remind us if you've heard this one before: Jonathan Stewart is battling injury, and it's unknown when he'll be back.
Yes, the Carolina Panthers running back is indeed hurt again, this time dealing with a hamstring ailment suffered before players reported to training camp.
Stewart, 27, isn't quite sure when he'll return to the field but guessed Saturday he could be back in two to four weeks, per The Charlotte Observer. However, he was adamant he would be ready for the regular season.
Stewart, of course, has been struck by a littany of injuries over the past two seasons. He played in just nine games in 2012 and then missed 10 contests in 2013. He underwent surgery on both ankles following the '12 season. Then, Stewart tore his MCL during the '13 season.
Given his history, it would be an upset if the oft-injured power back returned within his estimated timetable.