luckadjusted

Week 15 2025 · December 14, 2025

Colts at Seahawks, Week 15 2025: who deserved to win?

The Seahawks beat the Colts 18–16 and were the better team on the day: replayed with the same form, they win 8 of 10. The Colts had the bounces: 3rd & 4th downs alone were worth 9 points of win probability to the Colts.

Before kickoff the Seahawks were 84% favorites. The game turned on a luck play (Q4, 0:22 left): J. Myers made 56-yard field goal, worth 25 points of win probability to the Seahawks. The biggest single swing (Q4, 0:11 left): the Colts threw an interception-worthy pass, and it was picked.

Final

Indianapolis Colts 16
Seattle Seahawks 18

December 14, 2025 · Lumen Field · Closing line: Seahawks −13.5

Luck index +25 Seahawks about even · −25 Colts

Each team’s own plays from this game, resampled into new drives 4,000 times: with the way both teams actually played, how often does this performance win? How the replay works

Ten replays. Colts win 2, Seahawks win 8.

  1. 1 IND 30 SEA 17
  2. 2 IND 37 SEA 34
  3. 3 IND 20 SEA 23
  4. 4 IND 17 SEA 22
  5. 5 IND 21 SEA 29
  6. 6 IND 23 SEA 34
  7. 7 IND 17 SEA 31
  8. 8 IND 6 SEA 24
  9. 9 IND 10 SEA 31
  10. 10 IND 13 SEA 40

Three other ways to ask

Each answers a different question, so none of them replaces the replay above.

The closing betting line, turned into a probability. What everyone knew before the game.

The line plus what this game showed, weighted by how much one game can tell. It stays close to the line because one game says little.

Every kick, fumble bounce, drop, conversion and judgment call redrawn; everything else fixed. The narrowest view of luck.

How 4,000 replays ended

Colts win 25% of them, Seahawks 75%, counting the 4% still level after regulation as half each. The line is what actually happened: Seahawks by 2.

Show as a table
Final margin in the replaysShare of replays
Colts by 17+2.9%
Colts by 9–167.0%
Colts by 1–813.8%
Level after regulation3.9%
Seahawks by 1–825.9%
Seahawks by 9–1621.5%
Seahawks by 17+25.0%

Where the luck was

What the luck was worth

Every lucky and unlucky play, weighted by the moment it happened: its swing in win probability, added up by kind. A missed kick in a decided game counts for nothing; the same kick at the end of a tie game can be most of a win.

Swings add up across a game, so in one that went back and forth they can pass 100%. On the scoreboard the same luck was worth +3.5 points to the Colts: the final margin was Seahawks by 2, without the luck Seahawks by 5.5. Luck shares are the fitted ones (how much of each kind is luck).

The kicks

How likely each kicker was to make that kick (his own record, the distance and the weather), and what happened.

  • B. Grupe, 42 yds made · 82% expected
  • J. Myers, 47 yds made · 78% expected
  • B. Grupe, 54 yds made · 60% expected
  • J. Myers, 52 yds made · 70% expected
  • J. Myers, 46 yds made · 81% expected
  • J. Myers, 32 yds made · 96% expected
  • J. Myers, 30 yds made · 97% expected
  • B. Grupe, 60 yds made · 51% expected
  • J. Myers, 56 yds made · 63% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Colts 3 for 14 yards, Seahawks 5 for 34 yards

Every accepted flag, in order, and what it did to the helped team’s chance of winning at that moment, including any play it wiped out (points on the scoreboard in grey). A flag in a decided game is worth nothing; one at the turn of a close game can be worth most of a win. Judgment calls count toward luck, pre-snap fouls mostly don’t. How calls are valued

WhenFlagWin probability for
Q2 14:43 Offensive Offside on the Seahawks (AJ Barner), 5 yards, wiping out the play · pre-snap +6% IND +1.9 pts
Q2 10:03 Defensive Offside on the Seahawks (Boye Mafe), 5 yards · pre-snap +3% IND +0.3 pts
Q2 9:44 False Start on the Colts, 5 yards · pre-snap +4% SEA +0.7 pts
Q2 8:43 False Start on the Colts, 4 yards · pre-snap +2% SEA +1.0 pts
Q2 8:26 Illegal Block Above the Waist on the Seahawks (Eric Saubert), 10 yards +1% IND +0.8 pts
Q2 7:32 False Start on the Seahawks, 5 yards · pre-snap +2% IND +0.4 pts
Q3 8:12 Delay of Game on the Colts, 5 yards · pre-snap +3% SEA +0.5 pts
Q4 12:01 Defensive Pass Interference on the Seahawks (Josh Jobe), 9 yards +8% IND +1.5 pts

Colts penalties, every game · Seahawks penalties, every game · All teams, 2025

When it happened

Seahawks’ chance of winning

As low as 22% and as high as 100%. Numbers mark the biggest luck moments, listed below.

nflfastR’s in-game win probability. It ignores the betting line, so it starts near even. Shaded above the middle while the Seahawks were ahead in it, below while the Colts were.
#WhenWhat happenedWin probability forNext drive
1 Q3 11:20 The Seahawks converted 4th & 43rd & 4th downs · 46% expected +8% SEA SEA: Field goal
2 Q3 0:41 The Seahawks converted 3rd & 33rd & 4th downs · 52% expected +16% SEA SEA: Field goal
3 Q4 12:01 Defensive Pass Interference on the Seahawks (Josh Jobe), 9 yardsJudgment calls · 18 flags in 2054 snaps before, position avg 1 per 213 +8% IND IND: Punt
4 Q4 9:00 The Colts were stopped on 3rd & 53rd & 4th downs · 39% expected +9% SEA IND: Punt
5 Q4 1:55 The Colts converted 3rd & 73rd & 4th downs · 32% expected +12% IND IND: Field goal
6 Q4 0:52 B. Grupe made 60-yard field goalKicks · 51% expected for him, 24 of 36 from 45+ before +18% IND IND: Turnover
7 Q4 0:22 The game turned hereJ. Myers made 56-yard field goalKicks · 63% expected for him, 61 of 81 from 45+ before +25% SEA SEA: End of game
8 Q4 0:11 The Colts threw an interception-worthy pass, and it was pickedInterceptions · 50% expected to stay out of the defense's hands +44% SEA –

Missing players

Key players (usually on the field for half the snaps or more) who missed this game or part of it, valued by position and quality. The same players are missing in every replay, so this counts as luck in points only.

  • Daniel Jones (IND QB), out (IR), replaced by p.rivers · 2.4 pts
  • Braden Smith (IND T), out (IR) · 1.0 pts
  • Sauce Gardner (IND CB), out · 0.7 pts
  • DeForest Buckner (IND DT), out (IR) · 0.7 pts
  • Charvarius Ward (IND CB), out (IR) · 0.6 pts

Adjust the assumptions

Disagree with how much of a fumble bounce or a pass interference call is luck? Change it and the coin-flip replay reruns in your browser.

Only coin-flips re-rolled

Colts 6% · Seahawks 94%

Final margin
Seahawks by 2
Luck in points
3.5 for the Colts
Luck-adjusted margin
Seahawks by 5.5
Replay with same day's form
Colts 25% · Seahawks 75% unchanged: why
How much of each is luck?

0% treats it as skill, 100% as pure luck. The tick is our fit.

What counts

We tested momentum on 19,000 lucky breaks and found none, so it's off by default. Why

Flip a play

Force the other outcome, in this game and in every replay: a made kick becomes a miss, a stop becomes a conversion, a flag goes the other way.

About these numbers

Play-by-play and win probability from nflfastR via nflverse; kicks valued against each kicker’s own record; drops and interception-worthy throws from FTN charting; injuries from snap counts and injury reports.

Methodology and validation · All Week 15 2025 games · Colts · Seahawks

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