luckadjusted

Week 5 2021 · October 7, 2021

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

Rams at Seahawks, Week 5 2021: who deserved to win?

The Rams beat the Seahawks 26–17 and were the better team on the day: replayed with the same form, they win 7 of 10.

Before kickoff the Rams were 57% favorites. The biggest swing (Q3, 9:27 left): the Rams converted 3rd & 10, worth 22 points of win probability to the Rams.

Final

Los Angeles Rams 26
Seattle Seahawks 17

October 7, 2021 · Lumen Field · Closing line: Rams −2.5

Luck index +27 Rams lucky · −27 Seahawks

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. Rams win 7, Seahawks win 3.

  1. 1 LA 41 SEA 10
  2. 2 LA 40 SEA 17
  3. 3 LA 36 SEA 19
  4. 4 LA 40 SEA 27
  5. 5 LA 37 SEA 27
  6. 6 LA 24 SEA 17
  7. 7 LA 40 SEA 37
  8. 8 LA 51 SEA 54
  9. 9 LA 24 SEA 32
  10. 10 LA 17 SEA 38

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

Rams win 73% of them, Seahawks 27%, counting the 3% still level after regulation as half each. The line is what actually happened: Rams by 9.

Show as a table
Final margin in the replaysShare of replays
Rams by 17+29.5%
Rams by 9–1619.9%
Rams by 1–822.8%
Level after regulation2.5%
Seahawks by 1–812.1%
Seahawks by 9–168.1%
Seahawks by 17+5.1%

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 +3.1 points to the Rams: the final margin was Rams by 9, without the luck Rams by 5.9. 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.

  • M. Gay, 31 yds made · 95% expected
  • J. Myers, 35 yds missed · 93% expected
  • J. Myers, 32 yds made · 95% expected
  • M. Gay, 47 yds made · 76% expected
  • Extra point missed · 93% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Rams 5 for 85 yards, Seahawks 3 for 20 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 6:27 Defensive Holding on the Rams, 5 yards +3% SEA +0.8 pts
Q2 11:54 Delay of Game on the Rams, 5 yards · pre-snap +1% SEA +0.5 pts
Q2 10:07 Defensive Pass Interference on the Rams (Robert Rochell), 47 yards +10% SEA +3.1 pts
Q2 0:27 Roughing the Passer on the Rams (Aaron Donald), 15 yards +2% SEA +1.0 pts
Q2 0:16 Offensive Holding on the Seahawks, 10 yards, wiping out the play +13% LA +4.8 pts
Q4 14:13 Defensive Pass Interference on the Rams (Jalen Ramsey), 13 yards +4% SEA +1.3 pts
Q4 5:01 False Start on the Seahawks (Will Dissly), 5 yards · pre-snap 0% LA +0.5 pts
Q4 0:18 False Start on the Seahawks (Geno Smith), 5 yards · pre-snap 0% LA +0.1 pts

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

When it happened

Seahawks’ chance of winning

As low as 0% and as high as 82%. 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 Rams were.
#WhenWhat happenedWin probability forNext drive
1 Q1 3:06 The Seahawks were stopped on 4th & 23rd & 4th downs · 59% expected +9% LA SEA: Turnover
2 Q2 10:07 Defensive Pass Interference on the Rams (Robert Rochell), 47 yardsJudgment calls · 0 flags in 53 snaps before, position avg 1 per 213 +10% SEA SEA: Touchdown
3 Q2 0:16 Offensive Holding on the Seahawks, 10 yards, wiping out the playJudgment calls +13% LA LA: End of half
4 Q2 0:07 J. Myers missed 35-yard field goalKicks · 93% expected for him +11% LA SEA: Punt
5 Q3 9:27 The Rams converted 3rd & 103rd & 4th downs · 29% expected +22% LA LA: Touchdown
6 Q3 7:56 The Rams missed an extra pointKicks · extra points are made about 94% of the time +6% SEA LA: Touchdown
7 Q3 3:36 The Seahawks were stopped on 3rd & 53rd & 4th downs · 39% expected +6% LA SEA: Punt
8 Q4 4:14 The Seahawks converted 3rd & 103rd & 4th downs · 26% expected +6% 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.

  • Gerald Everett (SEA TE), out (IR) · 0.7 pts
  • Chris Carson (SEA RB), out · 0.3 pts
  • Ethan Pocic (SEA G/C), out (IR) · 0.2 pts
  • Cam Akers (LA RB), out (IR) · 0.1 pts
  • Justin Hollins (LA 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

Rams 83% · Seahawks 17%

Final margin
Rams by 9
Luck in points
3.1 for the Rams
Luck-adjusted margin
Rams by 5.9
Replay with same day's form
Rams 73% · Seahawks 27% 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 5 2021 games · Rams · Seahawks

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