SANTA CLARA, Calif. – The San Francisco 49ers' defense has evolved this season.In the recent past, the 49ers were famous for not rotating many players on defense. But injuries have given several young players a chance to play. The youngsters have helped keep up San Francisco's strong standard of defense; the unit has not slipped despite the infusion of youth.One of those players is defensive tackle Tony Jerod-Eddie. And it's likely he will get another chance to make a contribution Sunday against New Orleans.