SANTA CLARA, Calif. – San Francisco 49ers coach Jim Harbaugh admitted it's much nicer seeing his prized quarterback playing offense than it is to see him going on the defensive.Harbaugh said he was a bit nervous when quarterback Colin Kaepernick collided into Green Bay cornerback Tramon Williams after he made the stop on Williams on a 17-yard interception return in the 49ers' wild-card win. Williams pounded hard into Kaepernick on the play, seemingly to take advantage of the free collisions with the quarterback.