Williams (hamstring) won't participate in practice Tuesday, Nick Wagoner of ESPN.com reports.
Williams was hurt on the 49ers' first offensive play during Sunday's win over the Bears and never returned to the contest. While the All-Pro offensive tackle isn't going to practice Tuesday, head coach Kyle Shanahan said Williams does have a chance to play Saturday against Seattle. The winner of that contest will secure the No. 1 playoff seed in the NFC and earn a first-round bye, so it stands to reason that Williams will do everything he can to be on the field.