Week 3 injury updates put the San Francisco 49ers in a bind as Brock Purdy's availability for Sunday’s game against Arizona remains highly uncertain. Purdy is limited all week with toe/left shoulder issues and is unlikely to start, elevating the importance of depth at guard and receiver. Connor Colby’s groin and Jauan Jennings’ ankle/shoulder further thin the lineup, while Jordan Watkins’ calf adds another notch to the injury narrative. McCaffrey carries a heavier burden, backed by a rest-conscious defensive plan and a few uncertain blockers. On the other sideline, the Cardinals list a handful of doubtful or limited players up front and in the secondary, setting the stage for a Week 3 test of depth and game plans.