Smith, who would have been a senior, had a rocky career with the Tigers, marred by an arrest for third-degree assault in August of 2009 after he allegedly knocked a fellow student unconscious with a punch to the back of the head during a fight outside an area hotel.
Smith, who was suspended for one game for the incident, was later granted youthful offender status. He served an academic suspension for the Outback Bowl following the 2009 season but returned to be a key member of the Tigers' 2010 national championship team.
Although he had only one carry and caught 5 passes for 49 yards, he was also one of the team's top blockers, playing in all 14 games and staring five.
Smith finished his career with 182 rushing yards and one touchdown in addition to 25 receptions for 278 yards and another score.
Although he was never a big ballcarrier, Smith's departure further diminishes Auburn's backfield numbers. Mike Dyer and Onterio McCalebb are the only returning scholarship running backs. They'll be joined by incoming freshman Tre Mason this summer. Rising junior Anthony Morgan might also be at tailback.
Auburn might also consider keeping 290-pound redshirt freshman Ladarious Phillips in the backfield. The Tigers experimented with him at defensive tackle before the bowl game.