Sacks and short fields shaped San Francisco's narrow edge

The useful passing comparison in San Francisco's 32–29 win is not simply Sam Darnold's 195 yards against Brock Purdy's 189. It is what remained after sacks. Seattle's six-yard advantage in quarterback passing yards became a 13-yard deficit in team net passing yards: 162 against 175.

The reconciliation is exact. Darnold lost 33 yards on five sacks; Purdy lost 14 on three. Subtract those losses from their respective passing totals and the team figures follow. Seattle surrendered 19 more yards to sacks, enough to reverse the original comparison.

That distinction does not explain every difference between the offenses, much less establish why either quarterback was sacked. It does prevent a misleading description of their output. Darnold threw for more yards, but Seattle's passing game finished with less net yardage once its backward movement was included.

My reading is that the losses deserve more attention than the small advantage in gross passing yards. They are not a model's estimate of what might have happened. They are recorded yards removed from Seattle's progress. To see their practical consequence, there is a second-quarter possession in which San Francisco pushed Seattle backward twice—and still conceded points.

Seattle had first-and-10 at San Francisco's 21-yard line, trailing 14–10. An eight-yard completion had just converted third-and-seven. The next two plays changed the possession's terms.

Gracen Halton sacked Darnold for nine yards at 3:37 of the second quarter. Osa Odighizuwa followed with a seven-yard sack at 2:54. First-and-10 became second-and-19, then third-and-26. Emanuel Wilson's five-yard run left fourth-and-21, and Jason Myers made a 50-yard field goal to narrow the deficit to 14–13.

The successful kick matters. This was not a possession San Francisco stopped from scoring. But describing it only as a Seattle scoring possession would conceal the defense's contribution: two consecutive sacks substantially increased the distance Seattle needed before it settled for the kick.

The defensible conclusion is narrower than saying those sacks prevented a touchdown. That alternative outcome is unknowable. What happened is concrete enough: Seattle went from a fresh set of downs at the 21 to needing 26 yards on third down, then attempted a field goal from farther away. Halton and Odighizuwa made progress substantially harder without making the possession pointless. That is defensive value a scoring summary alone can miss.

The other side of that lost-ground story was how little field San Francisco had to cover after Seattle's first-half giveaways. All 21 of the 49ers' first-half points followed turnovers. Two sequences gave the offense short scoring opportunities; the third supplied a defensive touchdown directly.

Renardo Green's interception left San Francisco at Seattle's 18-yard line. The offense still had work to do: Purdy completed a 13-yard pass to Mike Evans on third-and-seven, then found Evans for the two-yard touchdown. A later Emanuel Wilson fumble left San Francisco at Seattle's 11. Christian McCaffrey scored from there on the next play.

Halton's contribution was different. With 13 seconds left in the half, he forced a fumble and recovered it for a touchdown. The extra point made the halftime score 21–13. No ensuing offensive possession was required.

Those distinctions matter. The first two takeaways created opportunities that San Francisco's offense converted; the third became points through the recovery itself. Treating the three scores as interchangeable offensive production would erase how they arose. The turnovers do not explain their own causes, and they did not alone determine the final result. They do explain why every San Francisco first-half scoring sequence began with Seattle surrendering the ball rather than the 49ers having to work across a long field.