Brock Purdy guided San Francisco down the field in the final quarter, and the 32-29 win that followed left Seattle with its first home loss in just over a year.
Across the first five games of the season, San Francisco's record stood unblemished, placing the team alongside two earlier Shanahan-led squads that had also opened at 5-0 — each of those prior editions going on to play in the Super Bowl.
Between the two sides, seven turnovers changed hands and personal fouls accumulated across multiple stoppages. Linebacker Dre Greenlaw of San Francisco was removed from the contest by officials and barred from returning. Both units held firm through three quarters before the offence took over in the final period.
Trailing by five points, San Francisco strung together a 12-play, 74-yard possession that Purdy capped with a seven-yard touchdown throw to Mike Evans, returning the lead to the 49ers. A pass to Evans from Purdy converted the 2-point attempt, lifting San Francisco's total to 29 against the opposition's 26.
Shanahan, speaking to reporters after the final whistle, described Brock's handling of the late possession as composed, even though the quarterback had moved through a stretch of inconsistency earlier — a stretch that ultimately mattered less than the eight-play, 43-yard march that produced a 44-yard field goal and, with Seattle having just converted one of its own, proved to be the difference in the final result.
A number of shortcomings were identified, and they ran deeper than a handful. On the Seahawks' last drive, the offense fell short on a fourth-and-10 conversion attempt, with the question of whether receiver Cooper Kupp managed to extend the ball past the first-down marker on that play remaining a point of contention among observers.
Facing a defense that ranked second across the league in expected points added per play, Purdy converted two early turnover opportunities into points, then guided the offense to two additional scoring drives as the fourth quarter played out.
Four receivers from the San Francisco roster had been placed on injured reserve by the time Sunday's game arrived. Samuel and Cowing both left the field with injuries, while Shanahan described the reserves who filled in as a group of fighters, noting that the roster's depth extends well beyond its most prominent players.
Evans finished with a personal-best seven receptions for 113 yards, adding a touchdown and the two-point conversion, while Purdy described him as a player who consistently lifts the offense, and Evans himself noted after the final whistle that the team had anticipated a hard-fought contest.
Purdy completed 19 of his 29 pass attempts for 189 yards, throwing for two touchdowns while also throwing one interception, as both teams demonstrated the caliber expected of top competition. Through five weeks of play, his arm had produced 13 touchdown passes against two interceptions. Of all the contests he played this season, only the one on Sunday brought his passer rating below the 100 threshold, with the final mark landing at 92.5.
Of San Francisco's five victories, three have come against opponents carrying winning records, and the team's point differential leads the entire NFL. Among those victories, a pair came at the expense of divisional opponents — Seattle and the Los Angeles Rams.