Packers coach Mike McCarthy says Clifton sustained a concussion in Sunday's victory over San Francisco but did not show any symptoms until Monday. Clifton was limited in practice Wednesday and his availability will be evaluated later this week. If Clifton can't play in Sunday's game at Detroit, second-year player T.J. Lang likely would replace him.
McCarthy says Woodson sprained his ankle during practice Wednesday. His availability is unclear.
Defensive end Cullen Jenkins already has been ruled out for Sunday's game with a calf injury.