Backup QB reps, o-line depth and defensive depth defined the 49ers' latest preseason drive against the Broncos. M. Jones and Morai offered mixed results, underscoring why SF relies on Brock Purdy as the anchor and a steady No. 2 behind him. Burford's rough day at left tackle amplified swing-tackle questions, while rookies like Chase Lucas and Malik Mustafa flashed in the back end, giving SF tangible depth signals. Nick Mullens's Jacksonville showing later in the episode highlighted how backup QBs in this system carve pro paths. Courtland Sutton reminded Denver of its weapons, while Trent Sherfield contributed veteran juice. Overall, SF can boast young DBs and depth, but October-ready protection and quarterback efficiency behind Purdy remain the focus.