Tim Hightower had been the Cardinals' top back, but he has been bothered by fumble trouble this year.
Wells was Arizona's first-round pick in 2009 out of Ohio State and rushed for 793 yards and seven touchdowns in his rookie season.
Hayes was on the physically unable to perform list and Schofield was on the non-football injury list.
Hayes, sidelined by a back injury, had 62 tackles in 14 games last season. Schofield, a fourth-round pick this year from Wisconsin, missed the Cardinals' offseason workouts and training camp after injuring his left knee at practice in preparation for the Senior Bowl.
Information from The Associated Press contributed to this report.