Dallas Cowboys linebacker Sean Lee is out for three or four weeks with a hamstring pull, ESPN.com reported Monday.
Lee was injured in the second quarter of Sunday's 49-17 loss to the New Orleans Saints.
Lee had an MRI on Monday. He said after the game that the injury was "not good."
Lee could miss just two games as the Cowboys have a bye this week. They return Nov. 24 against the New York Giants and then take on the Oakland Raiders on Nov. 28. If Lee misses two games, he will return Dec. 9 against the Chicago Bears.
Lee is the team leader in tackles and interceptions. He misses 10 games with a toe injury last year.
Justin Durant, who replaced Lee on Sunday, is also expected to miss three to four weeks with a hamstring strain. He was injured during the second half.
Ernie Sims was moved to middle linebacker and Kyle Bosworth played on the strong side.