luckadjusted

Week 17 2021 · January 2, 2022

No FTN charting for this game (drops and interception-worthy throws are not modelled).

Broncos at Chargers, Week 17 2021: who deserved to win?

The Chargers beat the Broncos 34–13, but it was a coin flip: replayed with the way both teams played, the Chargers win 5 of 10. Luck ran their way: injuries alone were worth 9.3 points to the Chargers.

Before kickoff the Chargers were 72% favorites. The biggest swing (Q2, 11:29 left): D. Hopkins made 19-yard field goal, worth 14 points of win probability to the Broncos.

Final

Denver Broncos 13
Los Angeles Chargers 34

January 2, 2022 · SoFi Stadium · Closing line: Chargers −8

Luck index +47 Chargers lucky · −47 Broncos

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 5, Chargers win 5.

  1. 1 DEN 28 LAC 9
  2. 2 DEN 27 LAC 15
  3. 3 DEN 31 LAC 24
  4. 4 DEN 23 LAC 19
  5. 5 DEN 30 LAC 28
  6. 6 DEN 27 LAC 29
  7. 7 DEN 14 LAC 19
  8. 8 DEN 27 LAC 35
  9. 9 DEN 6 LAC 19
  10. 10 DEN 10 LAC 33

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

Broncos win 47% of them, Chargers 53%, counting the 6% still level after regulation as half each. The line is what actually happened: Chargers by 21.

Show as a table
Final margin in the replaysShare of replays
Broncos by 17+8.0%
Broncos by 9–1613.5%
Broncos by 1–823.6%
Level after regulation6.4%
Chargers by 1–823.9%
Chargers by 9–1615.1%
Chargers by 17+9.6%

Where the luck was

Take the luck out

The final margin was Chargers by 21. Remove the luck, one kind at a time, and it becomes Chargers by 8.0.

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.

  • D. Hopkins, 19 yds made · 99% expected
  • B. McManus, 61 yds made · 60% expected
  • D. Hopkins, 23 yds made · 99% expected
  • B. McManus, 23 yds made · 100% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

When it happened

Chargers’ 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 Chargers were ahead in it, below while the Broncos were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:45 Defensive Pass Interference on the Broncos (Kyle Fuller), 14 yardsJudgment calls · 18 flags in 2959 snaps before, position avg 1 per 213 +6% LAC LAC: Touchdown
2 Q1 9:14 The Broncos converted 4th & 13rd & 4th downs · 76% expected +5% DEN DEN: Turnover on downs
3 Q1 7:07 The Broncos were stopped on 4th & 63rd & 4th downs · 39% expected +7% LAC DEN: Punt
4 Q1 2:30 The Chargers converted 3rd & 63rd & 4th downs · 39% expected +4% LAC LAC: Field goal
5 Q2 11:29 D. Hopkins made 19-yard field goalKicks · 99% expected for him +14% DEN LAC: Punt
6 Q2 6:01 The Broncos were stopped on 3rd & 23rd & 4th downs · 54% expected +6% LAC DEN: Turnover on downs
7 Q2 5:25 The Broncos were stopped on 4th & 23rd & 4th downs · 54% expected +4% LAC DEN: Field goal
8 Q2 3:24 The Broncos fumbled and the Chargers recoveredFumble bounces · loose balls are close to 50/50 +4% LAC DEN: Field goal

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.

  • Jared Cook (LAC TE), out (IR) · 0.6 pts
  • Drue Tranquill (LAC LB), out · 0.3 pts
  • Teddy Bridgewater (DEN QB), out, replaced by d.lock · 4.8 pts
  • Bobby Massie (DEN T), out (IR) · 0.8 pts
  • Ronald Darby (DEN CB), out · 0.7 pts
  • Jerry Jeudy (DEN WR), out (IR) · 0.6 pts
  • Tim Patrick (DEN WR), out (IR) · 0.6 pts
  • Calvin Anderson (DEN T), out (IR) · 0.4 pts
  • Jonathon Cooper (DEN LB), out (IR) · 0.4 pts
  • Bryce Callahan (DEN CB), out (IR) · 0.4 pts
  • Graham Glasgow (DEN G), out (IR) · 0.3 pts
  • Bradley Chubb (DEN LB), out (IR) · 0.3 pts
  • Baron Browning (DEN LB), out (IR) · 0.3 pts
  • Stephen Weatherly (DEN DE), out (IR) · 0.3 pts
  • Kenny Young (DEN 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

Broncos 0% · Chargers 100%

Final margin
Chargers by 21
Luck in points
13.0 for the Chargers
Luck-adjusted margin
Chargers by 8.0
Replay with same day's form
Broncos 47% · Chargers 53% 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 (not available for this game); injuries from snap counts and injury reports. No FTN charting for this game (drops and interception-worthy throws are not modelled).

Methodology and validation · All Week 17 2021 games · Broncos · Chargers

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