Dallas Cowboys defensive tackle Maliek Collins has been ruled out of Sunday's game at Seattle with a knee injury and pass rusher Randy Gregory is set to return after missing a week with a concussion.
Collins missed the preseason recovering from surgery for a broken foot sustained during offseason workouts. He injured the knee in last week's win over the New York Giants.
Gregory had missed 30 of the previous 32 games because of substance-abuse suspensions before sustaining a concussion in the season-opening loss at Carolina. He was a full participant in practice all week.