luckadjusted

Week 8 2021 · October 31, 2021

No FTN charting for this game (drops and interception-worthy throws are not modelled).

Jaguars at Seahawks, Week 8 2021: who deserved to win?

The Seahawks beat the Jaguars 31–7, but it was a coin flip: replayed with the way both teams played, the Seahawks win 6 of 10.

Before kickoff the Seahawks were 62% favorites. The biggest swing (Q1, 10:13 left): the Jaguars were stopped on 3rd & 9, worth 10 points of win probability to the Seahawks.

Final

Jacksonville Jaguars 7
Seattle Seahawks 31

October 31, 2021 · Lumen Field · Closing line: Seahawks −4

Luck index +43 Seahawks lucky · −43 Jaguars

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. Jaguars win 4, Seahawks win 6.

  1. 1 JAX 24 SEA 6
  2. 2 JAX 17 SEA 6
  3. 3 JAX 30 SEA 24
  4. 4 JAX 16 SEA 13
  5. 5 JAX 19 SEA 21
  6. 6 JAX 25 SEA 30
  7. 7 JAX 15 SEA 24
  8. 8 JAX 10 SEA 22
  9. 9 JAX 31 SEA 48
  10. 10 JAX 16 SEA 41

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

Jaguars win 43% of them, Seahawks 57%, counting the 2% still level after regulation as half each. The line is what actually happened: Seahawks by 24.

Show as a table
Final margin in the replaysShare of replays
Jaguars by 17+7.3%
Jaguars by 9–1614.0%
Jaguars by 1–819.6%
Level after regulation2.3%
Seahawks by 1–825.6%
Seahawks by 9–1616.7%
Seahawks by 17+14.6%

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 +2.2 points to the Jaguars: the final margin was Seahawks by 24, without the luck Seahawks by 26.2. Luck shares are the fitted ones (how much of each kind is luck).

Penalties: Jaguars 12 for 93 yards, Seahawks 5 for 40 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 8:12 Roughing the Passer on the Jaguars (DaVon Hamilton), 15 yards +1% SEA +1.1 pts
Q1 0:10 Delay of Game on the Jaguars, 5 yards · pre-snap +3% SEA +0.7 pts
Q2 13:00 Taunting on the Jaguars (Rayshawn Jenkins), 15 yards +3% SEA +1.7 pts
Q2 12:22 Delay of Game on the Seahawks, 5 yards · pre-snap +1% JAX +0.5 pts
Q2 9:31 Unsportsmanlike Conduct on the Seahawks (D.K. Metcalf), 15 yards +2% JAX +1.2 pts
Q2 2:41 Defensive Too Many Men on Field on the Jaguars, 5 yards · pre-snap 0% SEA +0.4 pts
Q2 1:54 Roughing the Passer on the Jaguars (Jihad Ward), 7 yards 0% SEA +2.2 pts
Q2 0:28 Defensive Offside on the Jaguars (K'Lavon Chaisson), 5 yards, wiping out the play · pre-snap +4% SEA +3.5 pts
Q3 8:09 Illegal Block Above the Waist on the Jaguars (Dakota Allen), 7 yards 0% SEA +0.7 pts
Q3 7:08 Illegal Formation on the Jaguars (Chapelle Russell), 5 yards · pre-snap 0% SEA +0.5 pts
Q3 4:58 Delay of Game on the Seahawks, 5 yards · pre-snap 0% JAX +0.4 pts
Q3 3:53 Delay of Game on the Jaguars, 5 yards · pre-snap 0% SEA +0.8 pts
Q4 14:02 Offensive Pass Interference on the Seahawks (Freddie Swain), 10 yards 0% JAX +1.4 pts
Q4 9:58 Defensive Holding on the Seahawks (Ugo Amadi), 5 yards, wiping out the play 0% JAX +2.3 pts
Q4 8:53 Offensive Holding on the Jaguars, 10 yards 0% SEA +2.1 pts
Q4 8:26 False Start on the Jaguars, 5 yards · pre-snap 0% SEA +0.4 pts
Q4 1:43 Offensive Holding on the Jaguars (Nevin Lawson), 9 yards 0% SEA +0.7 pts

Jaguars penalties, every game · Seahawks penalties, every game · All teams, 2021

When it happened

Seahawks’ chance of winning

As low as 49% 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 Jaguars were.
#WhenWhat happenedWin probability forNext drive
1 Q1 11:36 The Jaguars converted 3rd & 53rd & 4th downs · 39% expected +7% JAX JAX: Punt
2 Q1 10:13 The Jaguars were stopped on 3rd & 93rd & 4th downs · 27% expected +10% SEA JAX: Punt
3 Q1 5:02 The Seahawks were stopped on 3rd & 13rd & 4th downs · 65% expected +3% JAX SEA: Touchdown
4 Q1 4:22 The Seahawks converted 4th & 13rd & 4th downs · 64% expected +7% SEA SEA: Touchdown
5 Q1 2:57 The Jaguars were stopped on 3rd & 23rd & 4th downs · 58% expected +4% SEA JAX: Punt
6 Q1 0:10 Delay of Game on the Jaguars, 5 yardsPre-snap flags +3% SEA SEA: Touchdown
7 Q2 6:13 The Jaguars were stopped on 4th & 63rd & 4th downs · 34% expected +3% SEA JAX: End of half
8 Q2 0:28 Defensive Offside on the Jaguars (K'Lavon Chaisson), 5 yards, wiping out the playPre-snap flags · 3 flags in 809 snaps before, position avg 1 per 409 +4% SEA SEA: Field goal

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.

  • Russell Wilson (SEA QB), out (IR), replaced by g.smith · 6.7 pts
  • Chris Carson (SEA RB), out (IR) · 0.3 pts
  • A.J. Cann (JAX OL), out (IR) · 0.6 pts
  • A.J. Cann (JAX G), out (IR) · 0.4 pts
  • Brandon Linder (JAX G), out (IR) · 0.4 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

Jaguars 0% · Seahawks 100%

Final margin
Seahawks by 24
Luck in points
2.2 for the Jaguars
Luck-adjusted margin
Seahawks by 26.2
Replay with same day's form
Jaguars 43% · Seahawks 57% 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 (not available for this game); injuries from snap counts and injury reports. No FTN charting for this game (drops and interception-worthy throws are not modelled).

Methodology and validation · All Week 8 2021 games · Jaguars · Seahawks

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