With Williams out for Sunday's game against Washington, Sam Hurd moves into the starting lineup. The Cowboys were already without rookie receiver Dez Bryant, who was put on injured reserve two weeks ago with a broken right ankle.
Marion Barber missed his third straight game for the Cowboys because of a calf injury.
Rex Grossman is the starter for Washington. John Beck is listed as the emergency quarterback against the Cowboys but is expected to be the backup for the final two games of the season.