luckadjusted

Week 14 2023 · December 10, 2023

Broncos at Chargers, Week 14 2023: who deserved to win?

The Broncos beat the Chargers 24–7, and it was no fluke: replayed with the way both teams actually played, the Broncos win 9 of 10. The Chargers had the bounces: drops alone were worth 1.8 points to the Chargers.

An off day for the Chargers: their offense played far below its usual level. In a fresh game against the Broncos they would win 48% of the time; with this day’s form, 14%. The numbers

Before kickoff the Chargers were 59% favorites. The biggest swing (Q1, 5:07 left): the Chargers were stopped on 3rd & 7, worth 23 points of win probability to the Broncos.

Final

Denver Broncos 24
Los Angeles Chargers 7

December 10, 2023 · SoFi Stadium · Closing line: Chargers −3

Luck index +14 Broncos about even · −14 Chargers

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. Broncos win 9, Chargers win 1.

  1. 1 DEN 48 LAC 17
  2. 2 DEN 35 LAC 12
  3. 3 DEN 32 LAC 14
  4. 4 DEN 21 LAC 6
  5. 5 DEN 33 LAC 20
  6. 6 DEN 34 LAC 24
  7. 7 DEN 20 LAC 13
  8. 8 DEN 31 LAC 27
  9. 9 DEN 22 LAC 20
  10. 10 DEN 18 LAC 27

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.

An off day for the Chargers

Their offense played far below its usual level. In a fresh game against the Broncos they would win 48% of the time; with this day’s form, 14%.

34 points apart for the Chargers: the gap is how differently this game went from what the two teams usually are.

UnitThis gameUsual levelBetter or worse than usual
Broncos offenseEPA per play gained +0.06 +0.04 better by 0.01
Broncos defenseEPA per play allowed −0.54 +0.11 better by 0.64
Chargers offenseEPA per play gained −0.54 +0.10 worse by 0.63
Chargers defenseEPA per play allowed +0.06 +0.12 better by 0.06

EPA (expected points added) per play on competitive snaps, turnovers left out because they are valued as luck. Usual level: the team’s earlier games this season plus half of last season, pulled toward the league average. One team’s defense and the other team’s offense are the same snaps, so one game can’t fully say whose day it was; it shows how far this one was from both teams’ norms.

How 4,000 replays ended

Broncos win 86% of them, Chargers 14%, counting the 2% still level after regulation as half each. The line is what actually happened: Broncos by 17.

Show as a table
Final margin in the replaysShare of replays
Broncos by 17+46.3%
Broncos by 9–1621.8%
Broncos by 1–817.8%
Level after regulation1.8%
Chargers by 1–88.1%
Chargers by 9–163.2%
Chargers by 17+1.0%

Where the luck was

Take the luck out

The final margin was Broncos by 17. Remove the luck, one kind at a time, and it becomes Broncos by 11.8.

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).

When it happened

Chargers’ chance of winning

As low as 0% and as high as 67%. 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 Chargers were ahead in it, below while the Broncos were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:03 The Chargers were stopped on 3rd & 73rd & 4th downs · 34% expected +6% DEN LAC: Punt
2 Q1 12:10 The Broncos threw an interception-worthy pass, and it was pickedInterceptions · 47% expected to stay out of the defense's hands +5% LAC DEN: Punt
3 Q1 10:58 The Chargers were stopped on 3rd & 33rd & 4th downs · 43% expected +5% DEN LAC: Turnover on downs
4 Q1 10:52 The Chargers were stopped on 4th & 33rd & 4th downs · 43% expected +9% DEN LAC: Turnover
5 Q1 5:07 The Chargers were stopped on 3rd & 73rd & 4th downs · 34% expectedThe Chargers were intercepted on a well-placed throwInterceptions · 0% expected to stay out of the defense's hands +23% DEN LAC: Punt
6 Q2 2:42 J. Williams dropped a catchable passDrops · 2 drops on 50 catchable balls before this +5% LAC DEN: Punt
7 Q3 8:53 The Chargers were stopped on 3rd & 13rd & 4th downs · 73% expected +6% DEN LAC: Turnover on downs
8 Q3 8:11 The Chargers were stopped on 4th & 13rd & 4th downs · 72% expected +5% DEN LAC: 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.

  • Joey Bosa (LAC DE), out (IR) · 0.7 pts
  • Josh Palmer (LAC WR), out (IR) · 0.7 pts
  • Deane Leonard (LAC CB), out · 0.2 pts
  • Kareem Jackson (DEN SS), 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

Broncos 100% · Chargers 0%

Final margin
Broncos by 17
Luck in points
5.2 for the Broncos
Luck-adjusted margin
Broncos by 11.8
Replay with same day's form
Broncos 86% · Chargers 14% 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 14 2023 games · Broncos · Chargers

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