ESPN first reported Jacobs would join the NFC West champion 49ers. A person with knowledge of the negotiations confirmed the deal Wednesday, speaking on condition of anonymity because the team had yet to make a formal announcement. Jacobs was released March 9 by the Giants after he failed to reach agreement on a restructured deal.
The 29-year-old Jacobs ran for 571 yards and seven touchdowns last season as a backup to Ahmad Bradshaw. He is the fourth-leading rusher in franchise history with 4,849 yards, but saw his role diminish with the emergence of Bradshaw.
A fourth-round draft pick in 2005, Jacobs rushed for 56 touchdowns. He had 1,000-yard seasons in 2007 and 2008, but his carries and yardage dipped the past two seasons. He gained 823 yards in 2010, and had just 152 carries and a 3.8-yard average last season.
"It's been a great ride," Jacobs said.
Jacobs was drafted out of Southern Illinois. He began his college career at Coffeyville Community College and transferred to Auburn before finally settling in with the Salukis.