Williams (ankle) did not participate at the Seahawks' practice Thursday, John Boyle of the team's official site reports.
Williams was limited to open the week at Wednesday's practice, but he was unable to participant one day later. He is dealing with an ankle injury, but head coach Mike Macdonald said Monday that he expects Williams to play Sunday versus the 49ers. The defensive lineman will have one more chance to practice Friday and erase any concern about his availability for Week 5.