Cowboys LB Sean Lee underwent an MRI for a knee injury

As if the Dallas Cowboys didn’t have enough injury concerns with Tony Romo out for six to 10 weeks, their best defender has an issue of his own.

On Tuesday, head coach Jason Garrett revealed that linebacker Sean Lee is dealing with a knee injury that has kept him out of practice since last Thursday’s game against the Seattle Seahawks. Lee underwent an MRI on Monday and the results came back positive.

The team doesn’t believe Lee’s knee issue is a long-term one, but his history of injuries is well known. He missed all of 2014 with a torn ACL and has yet to play a full 16-game slate in his career.

A few hours prior to Garrett’s press conference, team owner Jerry Jones said Lee is “fine” and is “not hurt at all.” That sounds a bit different than Garrett, who acknowledged that there is some sort of injury there.

Dallas expects Lee to be on the field against the Giants in Week 1, but this is a situation worth keeping an eye on. He’s arguably the team’s best defensive player when healthy.