luckadjusted
NFL Week 9 · 2026

Week 7 2023 · October 22, 2023

Chargers at Chiefs, Week 7 2023: who deserved to win?

The Chiefs beat the Chargers 31–17, and the replays back it up: with the way both teams actually played, the Chiefs win 9 of 10.

Before kickoff the Chiefs were 66% favorites. The biggest swing (Q4, 11:51 left): Offensive Holding on the Chiefs, 4 yards, wiping out the play, worth 11 points of win probability to the Chargers.

Final

Los Angeles Chargers 17
Kansas City Chiefs 31

October 22, 2023 · GEHA Field at Arrowhead Stadium · Closing line: Chiefs −5.5

Luck index +10 Chiefs about even · −10 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. Chargers win 1, Chiefs win 9.

  1. 1 LAC 37 KC 31
  2. 2 LAC 28 KC 30
  3. 3 LAC 16 KC 20
  4. 4 LAC 21 KC 28
  5. 5 LAC 16 KC 27
  6. 6 LAC 37 KC 51
  7. 7 LAC 21 KC 38
  8. 8 LAC 23 KC 44
  9. 9 LAC 9 KC 35
  10. 10 LAC 14 KC 47

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

Chargers win 10% of them, Chiefs 90%, counting the 2% still level after regulation as half each. The line is what actually happened: Chiefs by 14.

Show as a table
Final margin in the replaysShare of replays
Chargers by 17+1.0%
Chargers by 9–162.1%
Chargers by 1–85.7%
Level after regulation1.8%
Chiefs by 1–818.0%
Chiefs by 9–1621.6%
Chiefs by 17+49.8%

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 +3.4 points to the Chargers: the final margin was Chiefs by 14, without the luck Chiefs by 17.4. 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.

  • H. Butker, 35 yds made · 94% expected
  • C. Dicker, 55 yds made · 62% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Chargers 4 for 43 yards, Chiefs 6 for 43 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 14:08 Defensive Pass Interference on the Chiefs (L'Jarius Sneed), 4 yards +4% LAC +1.0 pts
Q1 9:41 Illegal Block Above the Waist on the Chiefs, 10 yards +3% LAC +0.9 pts
Q1 8:21 Offensive Holding on the Chiefs, 10 yards +2% LAC +1.2 pts
Q2 13:26 Illegal Use of Hands on the Chargers, 10 yards, wiping out the play +3% KC +1.7 pts
Q2 0:42 Offensive Pass Interference on the Chiefs (Justyn Ross), 10 yards +1% LAC +1.2 pts
Q2 0:29 Defensive Pass Interference on the Chargers (Eric Kendricks), 23 yards +5% KC +3.1 pts
Q3 2:55 False Start on the Chiefs (Travis Kelce), 5 yards · pre-snap 0% LAC +0.4 pts
Q4 12:36 False Start on the Chargers (Derius Davis), 5 yards · pre-snap +1% KC +0.7 pts
Q4 11:51 Offensive Holding on the Chiefs, 4 yards, wiping out the play +11% LAC +3.3 pts
Q4 1:30 False Start on the Chargers, 5 yards · pre-snap 0% KC +0.4 pts

Chargers penalties, every game · Chiefs penalties, every game · All teams, 2023

When it happened

Chiefs’ chance of winning

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 Chiefs were ahead in it, below while the Chargers were.
#WhenWhat happenedWin probability forNext drive
1 Q1 3:51 The Chargers converted 3rd & 73rd & 4th downs · 35% expected +6% LAC LAC: Field goal
2 Q1 1:53 C. Dicker made a 55-yard field goalKicks · 62% expected for him, 5 of 7 from 45+ before +6% LAC LAC: Touchdown
3 Q2 7:11 The Chargers converted 3rd & 73rd & 4th downs · 28% expected +6% LAC LAC: Touchdown
4 Q2 5:06 The Chargers converted 3rd & 73rd & 4th downs · 36% expected +6% LAC LAC: Punt
5 Q2 0:29 Defensive Pass Interference on the Chargers (Eric Kendricks), 23 yardsJudgment calls · 5 flags in 4506 snaps before, position avg 1 per 444 +5% KC KC: Touchdown
6 Q3 2:32 The Chiefs converted 3rd & 163rd & 4th downs · 25% expected +7% KC KC: Punt
7 Q4 12:54 The Chiefs were stopped on 3rd & 33rd & 4th downs · 58% expected +5% LAC KC: Punt
8 Q4 11:51 Offensive Holding on the Chiefs, 4 yards, wiping out the playJudgment calls +11% LAC 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.

  • Mike Williams (LAC WR), out (IR) · 0.7 pts
  • Corey Linsley (LAC C), out (IR) · 0.7 pts
  • Alohi Gilman (LAC SS), out · 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

Chargers 0% · Chiefs 100%

Final margin
Chiefs by 14
Luck in points
3.4 for the Chargers
Luck-adjusted margin
Chiefs by 17.4
Replay with same day's form
Chargers 10% · Chiefs 90% 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; injuries from snap counts and injury reports.

Methodology and validation · All Week 7 2023 games · Chargers · Chiefs

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