Cowboys center Costa out 2-4 weeks

Dallas Cowboys center Phil Costa is expected to to-4 weeks after suffering a sprained posterior cruciate ligament in his right knee.

Costa sustained the injury, which should not require surgery, during Wednesday's evening session, causing him to miss Thursday's practice.

The setback means the Cowboys will have to look elsewhere for a backup to starting center Andre Gurode, who is himself recovering from arthroscopic knee surgery in July.

Dallas has two more preseason games remaining, this Saturday at Minnesota and September 1 at Miami, before beginning its regular season on September 11 on the road against the New York Jets.