Lewis, who was hurt during last weekend's loss in Denver, missed his third consecutive practice Friday, and the Browns listed him as doubtful on their injury report.
If Lewis can't go against his former team, rookie James Davis and Jerome Harrison likely will split the carries against the Ravens, who have the NFL's top run defense.
Davis was impressive during the preseason, but he sustained a shoulder injury against the Minnesota Vikings in the season opener and was inactive last week. Harrison missed the opener with a knee injury.
The Browns listed kicker Phil Dawson (right calf) as questionable, leading them to work out several free agents, who practiced field goals and kickoffs as they were videotaped by team personnel. Dawson hadn't appeared on the team's injury report the previous two days.
Dawson, the only player left from Cleveland's 1999 expansion season, has been remarkably consistent against Baltimore, making 24 of 26 field-goal attempts in 19 career games. Dawson's 216 career field goals are tied for second in team history behind Lou Groza (234).
The Associated Press contributed to this report.