San Francisco 49ers running back Brandon Jacobs turned in a full week of practice, but is officially listed as questionable on the team's official injury report.
Jacobs suffered a right knee injury during the 49ers' preseason game in Houston on Aug. 18 when he took a helmet directly to his left knee. At the time, the injury looked to be serious, but he suffered no significant structural damage and is in line to see his first regular season NFL action of 2012 in Week 5 against the Bills at home.
The 49ers have struggled in short yardage situations and on third down, converting just 14-of-42 third down opportunities through four games.
Jacobs figures to give starter Frank Gore some relief in that role and keep the primary running back's legs fresh for the rigors of a full season. The 6'4, 264 lb. Jacobs was acquired as a free agent after spending the beginning of his career as a member of the New York Giants, where he won two Super Bowl rings.