luckadjusted

Week 15 2023 · December 18, 2023

Eagles at Seahawks, Week 15 2023: who deserved to win?

The Seahawks stole one. They beat the Eagles 20–17, but replayed with the way both teams actually played, the Eagles win 8 of 10. Luck ran their way: 3rd & 4th downs alone were worth 10 points of win probability to the Seahawks.

Before kickoff the Eagles were 64% favorites. The biggest swing (Q4, 0:33 left): the Seahawks converted 3rd & 10, worth 50 points of win probability to the Seahawks.

Final

Philadelphia Eagles 17
Seattle Seahawks 20

December 18, 2023 · Lumen Field · Closing line: Eagles −5

Luck index +82 Seahawks very lucky · −82 Eagles

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. Eagles win 8, Seahawks win 2.

  1. 1 PHI 30 SEA 3
  2. 2 PHI 27 SEA 7
  3. 3 PHI 24 SEA 10
  4. 4 PHI 16 SEA 3
  5. 5 PHI 23 SEA 13
  6. 6 PHI 24 SEA 17
  7. 7 PHI 17 SEA 13
  8. 8 PHI 16 SEA 14
  9. 9 PHI 10 SEA 13
  10. 10 PHI 6 SEA 17

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

Eagles win 82% of them, Seahawks 18%, counting the 2% still level after regulation as half each. The line is what actually happened: Seahawks by 3.

Show as a table
Final margin in the replaysShare of replays
Eagles by 17+29.9%
Eagles by 9–1622.1%
Eagles by 1–828.1%
Level after regulation2.3%
Seahawks by 1–811.0%
Seahawks by 9–165.1%
Seahawks by 17+1.5%

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 +7.0 points to the Eagles: the final margin was Seahawks by 3, without the luck Seahawks by 10. 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.

  • J. Elliott, 27 yds made · 98% expected
  • J. Myers, 26 yds made · 98% expected
  • J. Myers, 43 yds made · 84% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Eagles 5 for 40 yards, Seahawks 5 for 35 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
Q1 6:31 False Start on the Seahawks (Will Dissly), 5 yards · pre-snap +1% PHI +0.8 pts
Q1 3:47 False Start on the Eagles (Jalen Hurts), 5 yards · pre-snap +2% SEA +0.6 pts
Q1 0:30 False Start on the Seahawks (Noah Fant), 5 yards · pre-snap +2% PHI +0.7 pts
Q1 0:05 Illegal Bat on the Seahawks (Jon Rhattigan), 10 yards +1% PHI +0.7 pts
Q2 7:19 False Start on the Eagles, 5 yards · pre-snap +1% SEA +1.4 pts
Q2 6:20 Defensive Pass Interference on the Eagles (Josh Jobe), 20 yards +4% SEA +1.1 pts
Q2 0:49 Intentional Grounding on the Seahawks (Drew Lock), 10 yards +3% PHI +0.7 pts
Q3 9:39 Illegal Use of Hands on the Seahawks (Jordyn Brooks), 5 yards +3% PHI +1.2 pts
Q3 2:43 False Start on the Eagles, 5 yards · pre-snap +1% SEA +0.6 pts
Q4 11:21 Defensive Pass Interference on the Eagles (James Bradberry), 5 yards +12% SEA +3.3 pts

Eagles penalties, every game · Seahawks penalties, every game · All teams, 2023

When it happened

Seahawks’ chance of winning

As low as 15% 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 Eagles were.
#WhenWhat happenedWin probability forNext drive
1 Q3 10:13 The Seahawks converted 3rd & 13rd & 4th downs · 72% expected +13% SEA SEA: Touchdown
2 Q3 7:22 The Eagles converted 3rd & 93rd & 4th downs · 34% expected +11% PHI PHI: Touchdown
3 Q4 11:21 Defensive Pass Interference on the Eagles (James Bradberry), 5 yardsJudgment calls · 18 flags in 5483 snaps before, position avg 1 per 216 +12% SEA SEA: Field goal
4 Q4 1:52 N. Fant dropped a catchable passDrops · 0 drops on 81 catchable balls before this +20% PHI SEA: Touchdown
5 Q4 1:00 T. Lockett dropped a catchable passDrops · 3 drops on 172 catchable balls before this +30% PHI SEA: Touchdown
6 Q4 0:56 The Seahawks converted 3rd & 103rd & 4th downs · 26% expected +18% SEA SEA: Touchdown
7 Q4 0:33 The Seahawks converted 3rd & 103rd & 4th downs · 26% expected +50% SEA SEA: Touchdown
8 Q4 0:13 The Eagles threw an interception-worthy pass, and it was pickedInterceptions · 47% expected to stay out of the defense's hands +40% 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.

  • Geno Smith (SEA QB), out, replaced by d.lock · 3.5 pts
  • Devon Witherspoon (SEA CB), out · 1.4 pts
  • Jamal Adams (SEA SS), out · 0.7 pts
  • Phil Haynes (SEA G), out (IR) · 0.2 pts
  • Darius Slay (PHI CB), out · 1.1 pts
  • Cam Jurgens (PHI G), out · 0.4 pts
  • Zach Cunningham (PHI LB), out · 0.3 pts
  • Nakobe Dean (PHI LB), out (IR) · 0.1 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

Eagles 14% · Seahawks 86%

Final margin
Seahawks by 3
Luck in points
7.0 for the Eagles
Luck-adjusted margin
Seahawks by 10.0
Replay with same day's form
Eagles 82% · Seahawks 18% 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 2023 games · Eagles · Seahawks

More from Week 15 2023