Zenner will likely share snaps with Justin Forsett and possibly Dwayne Washington (ankle) in Sunday's game against the Rams, ESPN.com reports.
Having already lost Ameer Abdullah (foot) to injured reserve, the Detroit backfield has only gotten messier in recent weeks, with Theo Riddick (ankle) ruled out for Sunday and Dwayne Washington (ankle) considered questionable. Zenner made the team as an undrafted free agent last year, and then stuck around as the No. 4 running back to start this season, after losing out to Washington for the goal-line/short-yardage role. Washington will likely serve as the lead back if he's healthy enough to do so, as Zenner's lack of quickness makes him a poor fit for regular work in a pass-first offense, while the 31-year-old Forsett has only been with the Lions since Tuesday. If Washington can't play, Forsett and Zenner will likely share snaps, with the former a better bet to catch passes and the latter a better bet for goal-line work.