Running back Steven Jackson never returned to Sunday's 31-24 victory over the St. Louis Rams after leaving with an injury. Coach Mike Smith announced Monday that defensive end Kroy Biermann is lost for the season with a torn Achilles tendon. A person informed of Jackson's injury tells NFL Media Insider Ian Rapoport that Jackson might miss 2 to 4 weeks with a thigh injury. The 30-year-old is officially viewed as "week to week." Source:NFL.com
