Dallas Cowboys inside linebacker Sean Lee was placed on season-ending injured reserve with a toe injury, and linebacker Ernie Sims was signed to take his place.
Lee will have surgery on his right big toe next week and is expected to be fully recovered for 2013.
Head coach Jason Garrett told reporters that the initially thought was that Lee would be out 4-6 weeks, but a second MRI on Tuesday confirmed extensive damage.
"Injuries are part of the NFL, as you know, in Dallas and 31 other cities," Garrett said. "We've had them. Everybody's had them. You have to deal with them through the season.
"Sean Lee is an outstanding football player. I can't tell you how well he's been playing since he's been our starting inside linebacker. He's the leader of the defense. He makes the calls. He plays the right way in practice. He plays the right way in the game. He defends the run. He defends the pass. He's a bell cow for us and a guy that really, really everybody on our defense and football team looks up to. He goes about it the right way and he's an outstanding person as well. We love everything about him. It's obviously unfortunate and disappointing that he had the injury."