Atlanta placed Smith on injured reserve Saturday due to an ankle injury, Scott Bair of the team's official site reports.
Smith likely sustained the ankle injury during practice this week, and after logging a DNP on Friday, the 31-year-old fullback has landed on IR. The veteran had appeared in 13 of the Falcons' 14 games before suffering this injury, recording 33 yards from scrimmage on three touches and playing 220 snaps on special teams.