49ers running back Frank Gore believes that teammate Vernon Davis needs to start showing some maturity. "It's his fourth year now. Now it's time," Gore said Saturday, according to the San Jose Mercury News. Davis was involved in a fight with a teammate at training camp recently, and the tight end also called out rookie wide receiver Michael Crabtree for holding out. San Francisco coach Mike Singletary made the entire team run sideline-to-sideline sprints following the fight. "I wasn't mad about having to run gassers," Gore said. "I just feel it's his fourth year now, and I told him it shouldn't be him now. Everybody makes mistakes but it shouldn't be him. OK, a rookie? I accept that."