Wells was limited in practice Thursday after sitting out Wednesday's workout.
Wells left Sunday's loss to Pittsburgh in the second quarter with the right knee sprain. The third-year pro from Ohio State had 42 yards on 12 carries before leaving for the locker room at the two-minute warning. Wells missed the third game of the season, at Seattle, with a hamstring injury.
Cardinals tight end Todd Heap was ruled out for Sunday's matchup against the Ravens, his former team.
Heap spent 10 seasons in Baltimore before signing as a free agent with Arizona this year. This will be the third straight game Heap will miss with a hamstring injury.
Jeff King will start in his place at tight end.
Information from The Associated Press was used in this report.