According to Josina Anderson, Williams says he is "all good," which we assume means he expects to play against the Rams. If he is healthy enough to go, that is a significant boost for quarterback Jimmy Garoppolo and the 49ers offense.
More good news is that the only other 49ers player listed as "questionable," running back Jeff Wilson Jr. (ankle), took part in pre-game warmups and looks to be ready to go.
Matt Barrows of The Athletic reports that Wilson was moving without a limp.
The 49ers and Rams will announce their inactive players 90 minutes before kickoff.