Lewis, who did not play in Sunday’s victory over the Cincinnati Bengals because of an injured toe on his right foot, has practiced on a limited basis in each of the past three days.
Lewis’ replacement on Sunday is also listed as questionable. Dannell Ellerbe has been limited the past three days by a balky hamstring.
Cornerback Chris Carr practiced Wednesday on a limited basis after a back ailment shelved him Monday and Tuesday. He is questionable, and so is rookie running back Anthony Allen (thigh) despite full participation in all three practices.
Safety Haruki Nakamura (thigh) was upgraded from limited to full participation Wednesday and is listed as probable.
The Ravens ruled out defensive tackle Arthur Jones, who has not practiced this week because of post-concussion symptoms.
For San Francisco, four starters were limited for the third consecutive day. Wide receivers Michael Crabtree (foot) and Braylon Edwards (knee), running back Frank Gore (knee) and right tackle Anthony Davis (ankle) are all probable for Thursday night.