The Seahawks finished the 2025 regular season as the NFL's #2 defense in EPA per play at -0.124, a full step behind Houston (-0.161) and just ahead of Minnesota (-0.101). Read one line down and the story of how they got there stops being a familiar one. Seattle wasn't second in pass-defense EPA — they were fifth (-0.117), behind HOU, MIN, CLE and JAX. What they were first in, and by a margin that stands out against a quarter-century of data, was stopping the run.

Table of Contents

1. The margin over the field
2. Where it came from: 2023 → 2024 → 2025
3. The gap-by-gap collapse
4. What it wasn't: the pass rush

1. The margin over the field

Seattle allowed -0.136 EPA per rush. Houston, at #2, allowed -0.077. That's a 0.059 EPA/play gap between the top run defense and the next-best one — and once you extend the query back to 2000, only four seasons show a larger #1-to-#2 separation in run-defense EPA/play: the 2000 Ravens (0.115), the 2007 Vikings (0.104), the 2002 Eagles (0.099), and the 2014 Lions (0.080). Every one of those is a defense people still talk about. Seattle's 2025 margin is the biggest since Ndamukong Suh's Detroit front eleven years ago.

The same dominance shows up in the raw numbers. Seattle allowed 3.93 yards per carry, the lowest figure in the league on 477 attempts. Houston was next at 4.00, then Indianapolis at 3.98 and Denver at 4.01. And Seattle's edge in EPA over Houston (0.059) is comparable in scale to the gap the #1 pass defense (HOU, -0.217) held over the #2 (MIN, -0.148) — roughly 0.07. When one team is separated from the field on any single dimension by that much, it's usually the identity of the whole unit.

2. Where it came from: 2023 → 2024 → 2025

Two years ago, Seattle's run defense was a liability. In 2023 they were +0.050 EPA per rush allowed — a bottom-tier number — on 4.69 YPC with an 11.9% explosive-run rate (10+ yard carries).

In 2024, under a new staff, they nudged forward to -0.021 EPA per rush but YPC actually ticked up to 4.70 and explosive runs stayed at 10.9%. That's still below-average against the run — closer to fixed than fixed.

2025 is where the floor dropped out from underneath opposing rushing games:

Explosive runs against Seattle were cut by a third year-over-year. YPC fell three-quarters of a yard. And the EPA swing (-0.115 in a single season) is what pushed the overall defense from middle-of-the-pack to elite.

3. The gap-by-gap collapse

What makes this a front-seven identity story and not one guy's story is that it happened everywhere on the line of scrimmage. Splitting rushes by location and gap, 2024 vs 2025:

Middle (runs charted between the tackles, no gap tag)

• 2024: 111 carries, 4.51 YPC, +0.009 EPA
• 2025: 163 carries, 3.60 YPC, -0.180 EPA

That's a two-hundred-point EPA swing on the highest-volume gap in football, on almost 50% more attempts. Opponents ran between the tackles more against Seattle in 2025 — and got demonstrably less for it.

Interior vs. edge, all rushes

• 2024 interior (middle + guard runs): 234 carries, 4.18 YPC, -0.122 EPA
• 2025 interior: 290 carries, 3.66 YPC, -0.169 EPA
• 2024 edge (tackle + end runs): 202 carries, 5.39 YPC, +0.098 EPA
• 2025 edge: 185 carries, 4.40 YPC, -0.073 EPA

The interior was already the strength in 2024 and got stronger. The edges — the actual weakness in 2024, where opponents were gaining a full yard per carry more than league average — became a net positive. Left tackle runs went from 6.00 YPC / +0.103 EPA to 4.16 YPC / -0.072 EPA. Right tackle: 5.07 / +0.131 to 4.39 / -0.224. Left end: 5.62 / +0.033 to 4.66 / +0.018. Every gap improved on EPA except one, and the biggest gains came in exactly the places 2024 opponents had been feasting.

4. What it wasn't: the pass rush

The natural next question is whether the run-defense jump is a downstream effect of a scarier pass rush. It isn't. Seattle's sack rate went from 7.32% in 2024 to 7.27% in 2025 — essentially flat, and 11th in the league. QB hit rate ticked from 17.7% to 16.8% — a slight decrease, though still 8th-best.

Those are respectable numbers. They aren't the story. Denver led the NFL in sack rate at 10.4% and QB hit rate at 22.4%; Minnesota was second in both; Cleveland third. Those are the teams whose 2025 defensive identity is "we hunt the quarterback." Seattle is decidedly not on that list — they finished fifth in pass-defense EPA on the strength of coverage, and behind their pass rush the pass-defense number (-0.117) is good, not extraordinary. The pass rush isn't what took this defense from average to #2.

What did is the thing that showed up on every single interior and edge run gap: opponents lost yards, lost EPA, and lost explosive plays trying to run the ball on Seattle. On a league-wide leaderboard where the #2 defense is 0.06 EPA/play behind, that's not a scheme wrinkle. That's the whole unit.

Numbers are from nflfastR play-by-play and team-season EPA aggregates, regular season only. Explosive-run rate defined as carries of 10+ yards. Run gap/location come from the play-by-play run_location and run_gap fields; interior = middle-tagged runs plus guard-gap runs, edge = tackle-gap plus end runs.