luckadjusted
NFL Week 9 · 2026

Week 17 2019 · December 29, 2019

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

Cardinals at Rams, Week 17 2019: who deserved to win?

The Rams beat the Cardinals 31–24, and the replays lean their way: with the same day's form, they win 6 of 10.

Before kickoff the Rams were 70% favorites. The biggest swing (Q2, 0:49 left): Offensive Pass Interference on the Cardinals (Damiere Byrd), 10 yards, wiping out the play, worth 12 points of win probability to the Rams.

Final

Arizona Cardinals 24
Los Angeles Rams 31

December 29, 2019 · Los Angeles Memorial Coliseum · Closing line: Rams −7

Luck index +38 Rams lucky · −38 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. Cardinals win 4, Rams win 6.

  1. 1 ARI 34 LA 13
  2. 2 ARI 20 LA 9
  3. 3 ARI 26 LA 20
  4. 4 ARI 21 LA 19
  5. 5 ARI 26 LA 28
  6. 6 ARI 19 LA 23
  7. 7 ARI 19 LA 26
  8. 8 ARI 17 LA 29
  9. 9 ARI 16 LA 33
  10. 10 ARI 10 LA 34

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

Cardinals win 38% of them, Rams 62%, counting the 2% 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
Cardinals by 17+6.7%
Cardinals by 9–1611.7%
Cardinals by 1–818.0%
Level after regulation1.7%
Rams by 1–824.9%
Rams by 9–1617.9%
Rams by 17+19.1%

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 +4.3 points to the Rams: the final margin was Rams by 7, without the luck Rams by 2.7. 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.

  • G. Zuerlein, 47 yds made · 79% expected
  • G. Zuerlein, 47 yds missed · 79% expected
  • Z. Gonzalez, 31 yds made · 96% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Cardinals 8 for 63 yards, Rams 10 for 91 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 half toward luck; pre-snap fouls, which repeat, don’t count. How calls are valued

WhenFlagWin probability for
Q1 7:22 Offensive Pass Interference on the Cardinals (Dan Arnold), 10 yards, wiping out the play +8% LA +2.7 pts
Q2 11:17 Defensive Holding on the Cardinals, 3 yards +5% LA +2.0 pts
Q2 10:02 Neutral Zone Infraction on the Rams (Clay Matthews), 5 yards · pre-snap +3% ARI +0.5 pts
Q2 5:28 Offensive Holding on the Rams, 10 yards +4% ARI +1.6 pts
Q2 2:27 Offensive Holding on the Rams (Cooper Kupp), 10 yards +4% ARI +0.9 pts
Q2 1:59 Roughing the Passer on the Cardinals (Michael Dogbe), 15 yards +2% LA +1.7 pts
Q2 0:49 Offensive Pass Interference on the Cardinals (Damiere Byrd), 10 yards, wiping out the play +12% LA +3.8 pts
Q2 0:26 Defensive Holding on the Rams, 5 yards +1% ARI +0.4 pts
Q3 11:40 False Start on the Rams (Cooper Kupp), 5 yards · pre-snap +1% ARI +0.6 pts
Q3 7:03 Illegal Contact on the Rams (Travin Howard), 6 yards +3% ARI +1.7 pts
Q3 6:58 Lowering the Head to Initiate Contact on the Rams (Taylor Rapp), 15 yards +3% ARI +1.0 pts
Q3 0:00 Neutral Zone Infraction on the Cardinals (Byron Murphy), 5 yards · pre-snap +5% LA +1.0 pts
Q4 11:36 Illegal Block Above the Waist on the Rams (Dante Fowler), 10 yards +1% ARI +0.7 pts
Q4 11:36 Delay of Game on the Cardinals, 5 yards · pre-snap +4% LA +0.9 pts
Q4 9:26 Offensive Holding on the Rams, 10 yards +1% ARI +0.9 pts
Q4 5:59 Roughing the Passer on the Rams (Clay Matthews), 15 yards +1% ARI +1.4 pts
Q4 3:09 Defensive Holding on the Cardinals (Byron Murphy), 5 yards +2% LA +0.8 pts
Q4 0:45 Offensive Holding on the Cardinals (J.R. Sweezy), 10 yards +2% LA +0.4 pts

Cardinals penalties, every game · Rams penalties, every game · All teams, 2019

When it happened

Rams’ chance of winning

As low as 36% 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 Rams were ahead in it, below while the Cardinals were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:43 The Rams converted 3rd & 83rd & 4th downs · 32% expected +7% LA LA: Field goal
2 Q1 12:23 The Rams converted 3rd & 133rd & 4th downs · 24% expected +7% LA LA: Field goal
3 Q1 7:22 Offensive Pass Interference on the Cardinals (Dan Arnold), 10 yards, wiping out the playJudgment calls · 0 flags in 97 snaps before, position avg 1 per 253 +8% LA LA: Turnover on downs
4 Q1 4:45 The Rams were stopped on 4th & 73rd & 4th downs · 35% expected +9% ARI LA: Punt
5 Q2 5:33 The Cardinals fumbled and the Rams recoveredFumble bounces · loose balls are close to 50/50 +8% LA ARI: Turnover
6 Q2 0:49 Offensive Pass Interference on the Cardinals (Damiere Byrd), 10 yards, wiping out the playJudgment calls · 1 flag in 412 snaps before, position avg 1 per 331 +12% LA LA: End of half
7 Q3 4:47 The Cardinals converted 3rd & 33rd & 4th downs · 43% expected +6% ARI ARI: Touchdown
8 Q4 13:37 The Rams converted 3rd & 43rd & 4th downs · 38% expected +12% LA LA: Touchdown

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.

  • Jalen Ramsey (LA CB), out · 1.6 pts
  • Rob Havenstein (LA T), out · 0.9 pts
  • Troy Hill (LA CB), out · 0.6 pts
  • Brian Allen (LA C), out (IR) · 0.2 pts
  • Rodney Gunter (ARI DE), out (IR) · 0.4 pts
  • Jonathan Bullard (ARI DE), out (IR) · 0.3 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

Cardinals 44% · Rams 56%

Final margin
Rams by 7
Luck in points
4.3 for the Rams
Luck-adjusted margin
Rams by 2.7
Replay with same day's form
Cardinals 38% · Rams 62% unchanged: why
How much of each is luck?

0% treats it as skill, 100% as pure luck. The tick is our fit.

What counts

None by default: our tests measured no carryover after a lucky break. Slide it up to count a break for more than its own swing. 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 17 2019 games · Cardinals · Rams

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