Cowboys' Sean Lee put on IR

IRVING, Texas -- Sean Lee's season is over.

The Dallas Cowboys announced they are placing the inside linebacker on season-ending injured reserve with a toe injury and have signed veteran linebacker Ernie Sims to fill his roster spot.

Lee will have surgery on his right big toe next week with a full recovery expected for 2013. Running back Felix Jones had a similar surgery in 2008 and has not had any issues with the toe since.

Coach Jason Garrett said the team initially believed Lee would miss 4-6 weeks with the injury, which was suffered in the third quarter Sunday at Carolina, but a second MRI on Tuesday confirmed extensive damage.

Lee's agent, Mike McCartney, said Wednesday morning that Lee would be seeking a second medical opinion, but that the linebacker suffered a "significant tear."

"We're not hopeful," McCartney added. "I'm sure he's having surgery sooner rather than later."

Lee leads the Cowboys in tackles with 77 in the first six games, according to the coaches' film. He has two tackles for loss, eight quarterback pressures, one interception, two pass deflections and a forced fumble.

"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."

The Cowboys plan on Lee being around the team for the rest of the season in a similar way Tony Romo remained with the club in 2010 as he recovered from a broken collarbone.

"He has so much intensity about him," Garrett said. "Talking to him yesterday, he's had injuries in the past and he's come back from all of them both in college and here in the NFL. And he has such an intensity about him. He said, 'You know, I'm not getting down. I'm ready to go. I'm going be part of this football team and we're going to get this thing fixed. I'll be back before you know it.' So he just has that way about him in everything he does. He's an outstanding human being and a great guy to have on your football team."

Sims, 27, played in 13 games last year for Indianapolis with four starts and was credited with 32 tackles. In 2010 he started 15 games for Philadelphia and had 55 tackles and two sacks. He spent his first four seasons with Detroit.

The Cowboys view Lee as a key piece of the future of the team, but he has had trouble staying healthy. He almost had his 2011 season come to an end with a dislocated left wrist but managed to miss only one game and played the rest of the season with a cast. He missed two games in 2010 with a hamstring injury after coming in with a knee injury.

Dan Connor will replace Lee in the starting lineup, and Bruce Carter will take over as the defensive signal-caller.

Dallas also put punter Chris Jones on injured reserve and signed safety Charlie Peprah.

Information from ESPNDallas.com's Calvin Watkins and The Associated Press was used in this report.