Phil Costa's impressive summer with the Dallas Cowboys has come to a frustrating conclusion.
The backup center missed Thursday's practice and was diagnosed with a sprained posterior cruciate ligament in his right knee, according to The Dallas Morning News.
Surgery has been ruled out, but Costa will be sidelined between two and four weeks. He could be out of the lineup for Dallas' regular season opener on Sept. 11 against the New York Jets.
Costa's injury comes at a time when his stock was rising within the organization. He had initially filled in at starting center as starter Andre Gurode recovered from offseason knee surgery, but Costa split starting reps even after Gurode returned to the field.
Costa is an undrafted second-year pro and Gurode is a five-time Pro Bowler, but Cowboys coach Jason Garrett had appeared open to finding a place for both players in the starting lineup if Costa continued to excel. Costa's injury has now pushed that scenario to the backburner.
