Coach Jim Harbaugh said he has no plans to change Brandon Jacobs' role. The 49ers have the league's No. 2 rushing offense and are averaging 5.88 yards per carry as a team. Harbaugh is not going to back off his rotation of Frank Gore and Kendall Hunter. "I think that's all decided on the field," he said when asked if Jacobs will be getting a chance anytime soon.