luckadjusted

Week 18 2022 · January 8, 2023

Cardinals at 49ers, Week 18 2022: who deserved to win?

The 49ers beat the Cardinals 38–13, and it was no fluke: replayed with the way both teams actually played, the 49ers win 10 of 10.

Before kickoff the 49ers were 85% favorites. The biggest swing (Q1, 5:26 left): the Cardinals were stopped on 4th & 1, worth 10 points of win probability to the 49ers.

Final

Arizona Cardinals 13
San Francisco 49ers 38

January 8, 2023 · Levi's Stadium · Closing line: 49ers −14

Luck index +5 49ers about even · −5 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 0, 49ers win 10.

  1. 1 ARI 20 SF 23
  2. 2 ARI 17 SF 23
  3. 3 ARI 13 SF 23
  4. 4 ARI 27 SF 40
  5. 5 ARI 24 SF 40
  6. 6 ARI 10 SF 30
  7. 7 ARI 3 SF 27
  8. 8 ARI 3 SF 30
  9. 9 ARI 10 SF 40
  10. 10 ARI 3 SF 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

Cardinals win 5% of them, 49ers 95%, counting the 1% still level after regulation as half each. The line is what actually happened: 49ers by 25.

Show as a table
Final margin in the replaysShare of replays
Cardinals by 17+0.3%
Cardinals by 9–160.9%
Cardinals by 1–83.0%
Level after regulation0.9%
49ers by 1–87.6%
49ers by 9–1618.3%
49ers by 17+68.9%

Where the luck was

Take the luck out

The final margin was 49ers by 25. Remove the luck, one kind at a time, and it becomes 49ers by 8.7.

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.

  • R. Gould, 27 yds made · 97% expected
  • Extra point missed · 93% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

When it happened

49ers’ chance of winning

As low as 39% 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 49ers were ahead in it, below while the Cardinals were.
#WhenWhat happenedWin probability forNext drive
1 Q1 10:49 The 49ers converted 3rd & 43rd & 4th downs · 46% expected +10% SF SF: Touchdown
2 Q1 9:59 The Cardinals were stopped on 3rd & 73rd & 4th downs · 30% expected +5% SF ARI: Punt
3 Q1 5:26 The Cardinals were stopped on 4th & 13rd & 4th downs · 70% expected +10% SF ARI: Punt
4 Q1 2:26 The Cardinals were stopped on 3rd & 103rd & 4th downs · 24% expected +3% SF ARI: Punt
5 Q2 13:59 The Cardinals threw an interception-worthy pass, and it was pickedInterceptions · 46% expected to stay out of the defense's hands +6% SF ARI: Touchdown
6 Q2 10:09 The Cardinals converted 3rd & 143rd & 4th downs · 19% expected +4% ARI ARI: Touchdown
7 Q2 7:29 The Cardinals converted 3rd & 113rd & 4th downs · 22% expected +6% ARI ARI: Touchdown
8 Q3 12:59 The 49ers converted 3rd & 173rd & 4th downs · 20% expected +4% SF SF: 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.

  • Jimmy Garoppolo (SF QB), out, replaced by b.purdy · 4.1 pts
  • Aaron Banks (SF G), out · 0.4 pts
  • Dre Greenlaw (SF LB), out · 0.3 pts
  • Kyler Murray (ARI QB), out (IR), replaced by d.blough · 4.7 pts
  • DeAndre Hopkins (ARI WR), out · 1.2 pts
  • Zach Allen (ARI DE), out · 1.0 pts
  • Budda Baker (ARI SS), out (IR) · 0.9 pts
  • Rondale Moore (ARI WR), out (IR) · 0.7 pts
  • Zach Ertz (ARI TE), out (IR) · 0.7 pts
  • Antonio Hamilton (ARI CB), out · 0.6 pts
  • James Conner (ARI RB), out · 0.5 pts
  • Marco Wilson (ARI CB), out · 0.4 pts
  • Zaven Collins (ARI LB), out · 0.4 pts
  • Aaron Brewer (ARI LS), 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

Cardinals 0% · 49ers 100%

Final margin
49ers by 25
Luck in points
16.3 for the 49ers
Luck-adjusted margin
49ers by 8.7
Replay with same day's form
Cardinals 5% · 49ers 95% 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 18 2022 games · Cardinals · 49ers

More from Week 18 2022