luckadjusted

Week 2 2024 · September 15, 2024

Rams at Cardinals, Week 2 2024: who deserved to win?

The Cardinals beat the Rams 41–10 and were the better team on the day: replayed with the same form, they win 8 of 10.

Before kickoff it was a pick’em.

Final

Los Angeles Rams 10
Arizona Cardinals 41

September 15, 2024 · State Farm Stadium · Closing line: Rams −1

Luck index +21 Cardinals about even · −21 Rams

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 2, Cardinals win 8.

  1. 1 LA 43 ARI 28
  2. 2 LA 17 ARI 13
  3. 3 LA 27 ARI 30
  4. 4 LA 16 ARI 20
  5. 5 LA 27 ARI 34
  6. 6 LA 17 ARI 27
  7. 7 LA 13 ARI 26
  8. 8 LA 23 ARI 38
  9. 9 LA 2 ARI 21
  10. 10 LA 13 ARI 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

Rams win 21% of them, Cardinals 79%, counting the 2% still level after regulation as half each. The line is what actually happened: Cardinals by 31.

Show as a table
Final margin in the replaysShare of replays
Rams by 17+2.4%
Rams by 9–166.2%
Rams by 1–812.2%
Level after regulation1.8%
Cardinals by 1–826.6%
Cardinals by 9–1621.1%
Cardinals by 17+29.8%

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 +10.6 points to the Cardinals: the final margin was Cardinals by 31, without the luck Cardinals by 20.4. 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. Karty, 29 yds made · 97% expected
  • M. Prater, 48 yds made · 79% expected
  • M. Prater, 57 yds made · 65% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Rams 2 for 10 yards, Cardinals 5 for 52 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 6:30 Offensive Holding on the Cardinals, 8 yards +1% LA +1.6 pts
Q1 5:18 Defensive Holding on the Rams (Quentin Lake), 5 yards +1% ARI +1.1 pts
Q2 12:16 Unnecessary Roughness on the Cardinals (Julian Okwara), 14 yards +1% LA +1.3 pts
Q2 6:10 False Start on the Cardinals, 5 yards · pre-snap 0% LA +0.8 pts
Q3 13:53 Offensive Holding on the Cardinals, 10 yards 0% LA +0.8 pts
Q3 0:41 Defensive Offside on the Rams (Tre'Davious White), 5 yards · pre-snap 0% LA +0.1 pts
Q4 8:10 Taunting on the Cardinals (Mack Wilson), 15 yards 0% LA +1.4 pts

Rams penalties, every game · Cardinals penalties, every game · All teams, 2024

When it happened

Cardinals’ chance of winning

As low as 48% 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 Cardinals were ahead in it, below while the Rams were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:40 The Rams were stopped on 3rd & 23rd & 4th downs · 62% expected +4% ARI LA: Turnover on downs
2 Q1 13:37 The Rams were stopped on 4th & 23rd & 4th downs · 61% expected +7% ARI LA: Punt
3 Q1 9:45 The Rams were stopped on 3rd & 43rd & 4th downs · 46% expected +5% ARI LA: Punt
4 Q1 3:35 The Cardinals converted 3rd & 53rd & 4th downs · 44% expected +3% ARI ARI: Touchdown
5 Q2 2:16 The Cardinals were stopped on 3rd & 73rd & 4th downs · 38% expected +2% LA ARI: Punt
6 Q2 1:23 The Rams converted 3rd & 83rd & 4th downs · 32% expected +2% LA LA: Turnover on downs
7 Q2 0:58 T. Atwell dropped a catchable passDrops · 3 drops on 67 catchable balls before this +2% ARI LA: Turnover on downs
8 Q2 0:05 The Rams were stopped on 4th & 43rd & 4th downs · 37% expected +2% ARI LA: Punt

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.

  • Carter O'Donnell (ARI T), out (IR) · 0.4 pts
  • Dante Stills (ARI DE), out · 0.3 pts
  • Puka Nacua (LA WR), out (IR) · 1.6 pts
  • Alaric Jackson (LA T), out (IR) · 0.6 pts
  • Tyler Higbee (LA TE), out (IR) · 0.6 pts
  • Steve Avila (LA 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

Rams 0% · Cardinals 100%

Final margin
Cardinals by 31
Luck in points
10.6 for the Cardinals
Luck-adjusted margin
Cardinals by 20.4
Replay with same day's form
Rams 21% · Cardinals 79% 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 2 2024 games · Rams · Cardinals

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