CHARLOTTE – Starting center Ryan Kalil (shoulder) and his backup Gino Gradkowski (knee) are both listed questionable for Sunday's game against the Kansas City Chiefs.

Kalil has not participated in practice all week. Gradkowski did not participate in Wednesday or Thursday's practice but returned on a limited basis on Friday.

"Gino had a good day. Ryan worked on the side with the trainers," said head coach Ron Rivera, who added that both players will be evaluated again on Saturday to see if they're fit to play.

The fact that Carolina has a quick turnaround before next week's Thursday night game against the New Orleans Saints will be a factor.

"A lot," Rivera said when asked about the impact of the short week. "That's the hard part when it comes to injuries. You have to be smart with the decisions that you make."

If Kalil and Gradkowski are both unavailable, Chris Scott will step in at center. Scott has played guard and tackle previously for Carolina.

"Chris is a very smart, bright guy," Rivera said. "We trust if we ever had to put him in at any of the positions that he'll fight and compete and do the best he can. That's all you can ask for."

Linebacker Shaq Thompson (knee), defensive tackle Vernon Butler (ankle) and defensive tackle Kyle Love (knee) are the other Panthers listed questionable.

Safety Colin Jones (concussion) joins offensive tackle Michael Oher (concussion) as players listed out.

Rivera said wide receiver Philly Brown will help fill Jones' void on special teams.

"He's tremendous," Rivera said of Brown's willingness to step in. "I can't say enough about his attitude and the way he performs out there during practice with the enthusiasm he plays with. It's fun to watch him compete."