SANTA CLARA, Calif. (AP) — When Steve Wilks was handed the reins of the NFL's stingiest defense in San Francisco, the priority for the new coordinator was learning what made the 49ers so good rather than installing his own system. Wilks stepped into what was both an easy job with a star-studded defense that led the NFL in points and yards allowed under DeMeco Ryans last season and a difficult one knowing he would get the blame if there is any regression. Coach Kyle Shanahan's main goal when looking for a new coordinator after Ryans left for the head coaching job in Houston was finding someone who would keep the structure intact.