"We need a guy who puts his foot in the ground and goes north and south," Harbaugh said. "To me, that fits this scheme. You really don't need a dancer. You don't need a sideways runner, although [Kansas City Chiefs Pro Bowl runner] Jamaal Charles has been in this system. He runs north and south, but he's fast as heck around the edge. It doesn't have to be a certain big guy, little guy, fast guy, slow guy.