Well, that was quick.
After a three-and-out by the Lions, the 49ers needed just four plays to strike first, scoring on a 21-yard pass from Alex Smith to tight end Vernon Davis.
After an incomplete pass, San Francisco picked up 30 yards on a reverse by wide receiver Mario Manningham. Smith then found wide out Michael Crabtree for a 17-yard completion.
The Lions should score quickly because this 49ers defense rarely gives up a big lead.