49ers on offense: Colin Kaepernick presents a unique challenge. The 49ers quarterback with the howitzer arm and the legs of a gazelle had his NFL coming-out party against the Packers last Saturday, throwing for 263 yards and rushing for 181 — including a 56-yard TD run. Kaepernick, who shrugged off an early pick-6, is extremely competitive. He is a great athlete and can demoralize a defense with his ability to improvise — just when you think he’s in your grasp, he’s escaped the pocket and moved the chains. He will make some poor decisions and poor throws, but he has talented receivers in Michael Crabtree (he has good speed and strong hands), Randy Moss (you know all about him), and tight end Vernon Davis (he’s a beast after the catch). Frank Gore is one of the toughest runners in the NFL. He runs low, with his shoulders square, and always finishes by delivering a blow. LaMichael James has excellent quickness and breakaway speed.

Falcons on defense: Atlanta has a talented trio of linebackers in Akeem Dent (a great name for a defender?), Sean Weatherspoon, and Stephen Nicholas. The secondary is loaded with ballhawks, including Asante Samuel and Thomas DeCoud.