Smith injured his left foot late in the first quarter of Wisconsin's 35-0 victory Saturday against Oregon State. Badgers coach Bret Bielema said Tuesday that Smith will use a redshirt this season and return as a fifth-year senior in 2012.
Smith started all 13 games in 2009, recording 55 tackles and 11 passes defended, before moving into a reserve role last season. The senior started the first two games this year.
Junior Marcus Cromartie relieved Smith in Saturday's game and will start this week against Northern Illinois. Cromartie has appeared in 13 career games with Wisconsin.
Adam Rittenberg covers Big Ten football for ESPN.com. He can be reached at firstname.lastname@example.org