Williams (hamstring) remained sidelined at practice Thursday, Daniel Popper of The Athletic reports.
Back-to-back absences have set the stage for what Williams does at practice Friday to be pivotal with regard to his Week 4 status. If the wideout is limited or out Sunday against the Buccaneers, added work behind top wide receiver Keenan Allen would be on tap for Jalen Guyton and KJ Hill.