San Francisco’s dominant victory over the Los Angeles Rams masked a glaring weakness: the 49ers’ run defense showed vulnerability against multi-tight end sets. Despite the presence of Nick Bosa and impressive pass rush success, the middle of the defensive line struggled to contain Rams’ back Blake Corum, who ripped off big gains before the Rams shifted their game plan. As the 49ers prepare to face the Miami Dolphins’ dynamic running back De'Von Achane, concerns linger about whether this defensive issue could become a recurring problem. In a timely move, the 49ers addressed their defensive line depth by signing McKinley Jackson, a former Bengals 3rd-round pick renowned for his run-stopping skills at Texas A&M. With Alfred Collins sidelined and a cast of untested tackles behind standout Osa Odighizuwa, can Jackson help shore up the interior and tip the balance in upcoming matchups? Week 2 against Miami offers an immediate test for this new-look unit.