luckadjusted

Week 14 2021 · December 13, 2021

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

Rams at Cardinals, Week 14 2021: who deserved to win?

The Rams beat the Cardinals 30–23 and were the better team on the day: replayed with the same form, they win 7 of 10. The Cardinals had the bounces: injuries alone were worth 3.6 points to the Cardinals.

Before kickoff the Cardinals were 59% favorites. The biggest swing (Q4, 0:34 left): Offensive Holding on the Cardinals, 10 yards, wiping out the play, worth 21 points of win probability to the Rams.

Final

Los Angeles Rams 30
Arizona Cardinals 23

December 13, 2021 · State Farm Stadium · Closing line: Cardinals −3

Luck index +30 Rams lucky · −30 Cardinals

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, Cardinals win 3.

  1. 1 LA 36 ARI 10
  2. 2 LA 25 ARI 6
  3. 3 LA 31 ARI 17
  4. 4 LA 23 ARI 12
  5. 5 LA 34 ARI 26
  6. 6 LA 31 ARI 27
  7. 7 LA 26 ARI 24
  8. 8 LA 24 ARI 27
  9. 9 LA 13 ARI 20
  10. 10 LA 10 ARI 27

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 70% of them, Cardinals 30%, counting the 4% still level after regulation as half each. The line is what actually happened: Rams by 7.

Show as a table
Final margin in the replaysShare of replays
Rams by 17+20.8%
Rams by 9–1621.6%
Rams by 1–826.3%
Level after regulation3.8%
Cardinals by 1–816.1%
Cardinals by 9–167.8%
Cardinals by 17+3.5%

Where the luck was

Take the luck out

The final margin was Rams by 7. Remove the luck, one kind at a time, and it becomes Rams by 10.3.

Each row takes one kind of luck out of the margin. Color shows which team it helped. Luck shares are the fitted ones (how much of each component 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. Prater, 53 yds made · 63% expected
  • M. Gay, 55 yds made · 63% expected
  • M. Gay, 35 yds made · 92% expected
  • M. Prater, 53 yds made · 64% expected
  • M. Gay, 33 yds made · 94% expected
  • M. Prater, 49 yds made · 71% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

When it happened

Cardinals’ chance of winning

As low as 0% and as high as 75%. 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 Cardinals were ahead in it, below while the Rams were.
#WhenWhat happenedWin probability forNext drive
1 Q2 8:53 The Rams converted 3rd & 83rd & 4th downs · 31% expected +9% LA LA: Field goal
2 Q2 3:22 The Cardinals converted 4th & 13rd & 4th downs · 65% expected +12% ARI ARI: Touchdown
3 Q2 2:00 The Rams converted 3rd & 43rd & 4th downs · 46% expected +14% LA LA: Field goal
4 Q2 0:10 The Cardinals converted 3rd & 73rd & 4th downs · 33% expected +12% ARI ARI: Field goal
5 Q2 0:01 M. Prater made 53-yard field goalKicks · 64% expected for him, 24 of 36 from 45+ before +8% ARI ARI: Turnover
6 Q3 4:44 The Cardinals were stopped on 4th & 23rd & 4th downs · 59% expected +8% LA ARI: Touchdown
7 Q4 0:37 Onside kick recovered by the CardinalsSpecial teams +7% ARI ARI: End of game
8 Q4 0:34 Offensive Holding on the Cardinals, 10 yards, wiping out the playJudgment calls +21% LA –

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.

  • J.J. Watt (ARI DE), out (IR) · 1.3 pts
  • Justin Pugh (ARI G), out · 0.4 pts
  • Chase Edmonds (ARI RB), out (IR) · 0.1 pts
  • Beau Brinkley (ARI LS), out · 0.1 pts
  • Jalen Ramsey (LA CB), out (IR) · 1.5 pts
  • Robert Woods (LA WR), out (IR) · 1.0 pts
  • Rob Havenstein (LA T), out (IR) · 1.0 pts
  • Tyler Higbee (LA TE), out (IR) · 0.9 pts
  • Donte Deayon (LA CB), out (IR) · 0.6 pts
  • Brian Allen (LA C), out · 0.3 pts
  • Darrell Henderson (LA RB), out (IR) · 0.2 pts
  • Terrell Lewis (LA LB), out · 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 82% · Cardinals 18%

Final margin
Rams by 7
Luck in points
3.3 for the Cardinals
Luck-adjusted margin
Rams by 10.3
Replay with same day's form
Rams 70% · Cardinals 30% 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 14 2021 games · Rams · Cardinals

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