Charlotte, N.C. — The Carolina Panthers announced Tuesday afternoon that All-Pro center Ryan Kalil and reserve center Gino Gradkowski have been placed on injured reserve.
Kalil did not make the trip to Oakland on Sunday due to a shoulder injury, which has forced the Pro Bowl center to miss three games in the last four weeks.
Gradkowski – starting in place of Kalil – injured his knee in the third quarter against the Raiders, the same knee that forced him to miss the team's contest against New Orleans in Week 11.
Carolina right tackle Daryl Williams also left the game Sunday due to an ankle injury.