luckadjusted

Week 15 2024 · December 15, 2024

Patriots at Cardinals, Week 15 2024: who deserved to win?

The Cardinals beat the Patriots 30–17 and were the better team on the day: replayed with the same form, they win 8 of 10.

Before kickoff the Cardinals were 67% favorites. The biggest swing (Q1, 12:24 left): Offensive Holding on the Patriots, 10 yards, wiping out the play, worth 12 points of win probability to the Cardinals.

Final

New England Patriots 17
Arizona Cardinals 30

December 15, 2024 · State Farm Stadium · Closing line: Cardinals −6

Luck index +22 Cardinals about even · −22 Patriots

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. Patriots win 2, Cardinals win 8.

  1. 1 NE 24 ARI 13
  2. 2 NE 23 ARI 20
  3. 3 NE 10 ARI 13
  4. 4 NE 13 ARI 17
  5. 5 NE 17 ARI 24
  6. 6 NE 13 ARI 23
  7. 7 NE 3 ARI 16
  8. 8 NE 7 ARI 24
  9. 9 NE 6 ARI 27
  10. 10 NE 9 ARI 37

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

Patriots win 22% of them, Cardinals 78%, counting the 4% still level after regulation as half each. The line is what actually happened: Cardinals by 13.

Show as a table
Final margin in the replaysShare of replays
Patriots by 17+2.1%
Patriots by 9–165.9%
Patriots by 1–814.0%
Level after regulation4.3%
Cardinals by 1–825.8%
Cardinals by 9–1622.9%
Cardinals by 17+25.1%

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 +13.6 points to the Cardinals: the final margin was Cardinals by 13, without the luck Patriots by 0.6. 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. Slye, 53 yds missed · 68% expected
  • C. Ryland, 49 yds made · 70% expected
  • J. Slye, 50 yds made · 72% expected
  • C. Ryland, 35 yds made · 92% expected
  • C. Ryland, 40 yds made · 87% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Patriots 4 for 45 yards, Cardinals 4 for 35 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 12:24 Offensive Holding on the Patriots, 10 yards, wiping out the play +12% ARI +3.3 pts
Q1 11:55 Defensive Offside on the Cardinals (Baron Browning), 5 yards · pre-snap +5% NE +0.3 pts
Q2 1:13 Offensive Pass Interference on the Cardinals (Trey McBride), 10 yards, wiping out the play +5% NE +1.7 pts
Q2 1:07 Defensive Holding on the Patriots (Jonathan Jones), 5 yards, wiping out the play +2% NE +0.8 pts
Q2 1:01 Offensive Holding on the Cardinals, 10 yards +2% NE +0.7 pts
Q3 11:36 Horse Collar Tackle on the Patriots (Deatrich Wise Jr.), 15 yards, wiping out the play +5% ARI +2.4 pts
Q3 11:08 Offensive Holding on the Cardinals (Trey McBride), 10 yards, wiping out the play +3% NE +1.7 pts
Q3 4:03 Roughing the Passer on the Patriots (Anfernee Jennings), 15 yards, wiping out the play +7% ARI +6.3 pts

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

When it happened

Cardinals’ chance of winning

As low as 47% 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 Patriots were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:49 The Patriots fumbled and recovered it themselvesFumble bounces · loose balls are close to 50/50 +6% NE NE: Missed field goal
2 Q1 12:24 Offensive Holding on the Patriots, 10 yards, wiping out the playJudgment calls +12% ARI ARI: Field goal
3 Q1 11:55 Defensive Offside on the Cardinals (Baron Browning), 5 yardsPre-snap flags · 14 flags in 1872 snaps before, position avg 1 per 445 +5% NE NE: Missed field goal
4 Q1 10:44 J. Slye missed 53-yard field goalKicks · 68% expected for him, 43 of 66 from 45+ before +8% ARI NE: Punt
5 Q1 5:55 The Patriots were stopped on 3rd & 193rd & 4th downs · 17% expectedThe Patriots fumbled and recovered it themselvesFumble bounces · loose balls are close to 50/50 +6% NE NE: Punt
6 Q2 0:46 The Cardinals converted 3rd & 113rd & 4th downs · 26% expected +7% ARI ARI: Field goal
7 Q3 4:59 The Patriots were stopped on 4th & 13rd & 4th downs · 65% expected +5% ARI NE: Turnover
8 Q3 4:03 Roughing the Passer on the Patriots (Anfernee Jennings), 15 yards, wiping out the playJudgment calls · 4 flags in 2322 snaps before, position avg 1 per 445 +7% ARI ARI: 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.

  • Blake Gillikin (ARI P), out (IR) · 0.2 pts
  • Marte Mapu (NE LB), out · 0.2 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

Patriots 56% · Cardinals 44%

Final margin
Cardinals by 13
Luck in points
13.6 for the Cardinals
Luck-adjusted margin
Patriots by 0.6
Replay with same day's form
Patriots 22% · Cardinals 78% 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 15 2024 games · Patriots · Cardinals

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