luckadjusted

Week 8 2023 · October 29, 2023

Bengals at 49ers, Week 8 2023: who deserved to win?

The Bengals stole one. They beat the 49ers 31–17, but replayed with the way both teams actually played, the 49ers win 9 of 10. Luck ran their way: drops alone were worth 2.2 points to the Bengals.

Before kickoff the 49ers were 62% favorites. The biggest swing (Q2, 0:13 left): the 49ers converted 3rd & 10, worth 11 points of win probability to the 49ers.

Final

Cincinnati Bengals 31
San Francisco 49ers 17

October 29, 2023 · Levi's Stadium · Closing line: 49ers −4

Luck index +86 Bengals very lucky · −86 49ers

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. Bengals win 1, 49ers win 9.

  1. 1 CIN 20 SF 13
  2. 2 CIN 27 SF 29
  3. 3 CIN 26 SF 31
  4. 4 CIN 30 SF 37
  5. 5 CIN 23 SF 33
  6. 6 CIN 24 SF 38
  7. 7 CIN 13 SF 30
  8. 8 CIN 16 SF 36
  9. 9 CIN 17 SF 42
  10. 10 CIN 0 SF 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

Bengals win 14% of them, 49ers 86%, counting the 2% still level after regulation as half each. The line is what actually happened: Bengals by 14.

Show as a table
Final margin in the replaysShare of replays
Bengals by 17+1.3%
Bengals by 9–163.7%
Bengals by 1–87.7%
Level after regulation1.7%
49ers by 1–817.4%
49ers by 9–1619.9%
49ers by 17+48.3%

Where the luck was

Take the luck out

The final margin was Bengals by 14. Remove the luck, one kind at a time, and it becomes Bengals by 8.5.

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.

  • E. McPherson, 50 yds missed · 73% expected
  • J. Moody, 36 yds made · 91% expected
  • E. McPherson, 56 yds made · 62% 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 0% and as high as 58%. 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 Bengals were.
#WhenWhat happenedWin probability forNext drive
1 Q1 12:49 The Bengals fumbled and recovered it themselvesFumble bounces · loose balls are close to 50/50 +6% CIN CIN: Touchdown
2 Q1 11:29 The Bengals converted 3rd & 103rd & 4th downs · 29% expected +6% CIN CIN: Touchdown
3 Q2 4:30 Offensive Holding on the 49ers (Jauan Jennings), 10 yards, wiping out the playJudgment calls · 6 flags in 1283 snaps before, position avg 1 per 420 +7% CIN CIN: Turnover
4 Q2 0:38 The Bengals fumbled and the 49ers recoveredFumble bounces · loose balls are close to 50/50 +7% SF CIN: Field goal
5 Q2 0:13 The 49ers converted 3rd & 103rd & 4th downs · 27% expected +11% SF SF: Punt
6 Q3 9:19 The 49ers got away with an interception-worthy throwInterceptions · 49% expected to stay out of the defense's hands +8% SF SF: Punt
7 Q3 8:34 The 49ers were stopped on 3rd & 73rd & 4th downs · 34% expectedG. Kittle dropped a catchable passDrops · 1 drops on 108 catchable balls before this +7% CIN SF: Punt
8 Q4 13:29 The Bengals were stopped on 3rd & 73rd & 4th downs · 36% expectedJ. Chase dropped a catchable passDrops · 4 drops on 189 catchable balls before this +7% SF CIN: 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.

  • Deebo Samuel (SF WR), out · 1.2 pts
  • Trent Williams (SF T), out · 1.1 pts
  • Jackson Carman (CIN G), 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

Bengals 92% · 49ers 8%

Final margin
Bengals by 14
Luck in points
5.5 for the Bengals
Luck-adjusted margin
Bengals by 8.5
Replay with same day's form
Bengals 14% · 49ers 86% 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 8 2023 games · Bengals · 49ers

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