Brock Purdy has opened the 2026 NFL season with an elite efficiency surge for the 4-0 San Francisco 49ers, throwing 11 passing touchdowns against one interception through four games while taking zero sacks. His 126.2 passer rating and league-leading EPA per dropback reflect clean pocket time and precise execution within Kyle Shanahan’s scheme, supported by Christian McCaffrey and George Kittle despite mounting injuries to the supporting cast. The immediate test arrives in Week 5 against Seattle’s top-ranked defense, which has limited explosive plays historically. Over the full regular season, Purdy’s durability, the 49ers’ offensive line protection, game-script volume, and remaining schedule strength will determine whether the early pace sustains or normalizes against stronger defenses.