luckadjusted

Week 9 2021 · November 7, 2021

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

Bills at Jaguars, Week 9 2021: who deserved to win?

The Jaguars beat the Bills 9–6, but it was a coin flip: replayed with the way both teams played, the Jaguars win 4 of 10. Luck ran their way: judgment calls alone were worth 10.4 points to the Jaguars.

Before kickoff the Bills were 86% favorites. The biggest swing (Q4, 5:41 left): the Bills were stopped on 3rd & 2, worth 37 points of win probability to the Jaguars.

Final

Buffalo Bills 6
Jacksonville Jaguars 9

November 7, 2021 · TIAA Bank Stadium · Closing line: Bills −14.5

Luck index +59 Jaguars lucky · −59 Bills

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. Bills win 6, Jaguars win 4.

  1. 1 BUF 23 JAX 2
  2. 2 BUF 24 JAX 9
  3. 3 BUF 17 JAX 6
  4. 4 BUF 13 JAX 6
  5. 5 BUF 26 JAX 21
  6. 6 BUF 26 JAX 24
  7. 7 BUF 10 JAX 12
  8. 8 BUF 0 JAX 6
  9. 9 BUF 24 JAX 34
  10. 10 BUF 3 JAX 20

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

Bills win 59% of them, Jaguars 41%, counting the 2% still level after regulation as half each. The line is what actually happened: Jaguars by 3.

Show as a table
Final margin in the replaysShare of replays
Bills by 17+12.6%
Bills by 9–1616.3%
Bills by 1–829.7%
Level after regulation2.5%
Jaguars by 1–820.6%
Jaguars by 9–1612.9%
Jaguars by 17+5.5%

Where the luck was

Take the luck out

The final margin was Jaguars by 3. Remove the luck, one kind at a time, and it becomes Bills by 5.2.

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.

  • M. Wright, 39 yds made · 86% expected
  • T. Bass, 24 yds made · 98% expected
  • T. Bass, 41 yds made · 83% expected
  • M. Wright, 55 yds made · 58% expected
  • M. Wright, 42 yds missed · 81% expected
  • M. Wright, 21 yds made · 99% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

When it happened

Jaguars’ chance of winning

As low as 38% 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 Jaguars were ahead in it, below while the Bills were.
#WhenWhat happenedWin probability forNext drive
1 Q1 11:00 The Jaguars converted 4th & 23rd & 4th downs · 55% expected +16% JAX JAX: Field goal
2 Q2 1:51 The Jaguars converted 3rd & 73rd & 4th downs · 29% expected +11% JAX JAX: Turnover
3 Q3 10:13 The Bills were stopped on 3rd & 33rd & 4th downs · 53% expected +13% JAX BUF: Turnover
4 Q3 4:11 The Bills converted 3rd & 223rd & 4th downs · 18% expected +10% BUF BUF: Turnover
5 Q3 2:02 The Bills were stopped on 3rd & 123rd & 4th downs · 26% expected +9% JAX BUF: Punt
6 Q4 5:41 The Bills were stopped on 3rd & 23rd & 4th downs · 62% expectedThe Bills fumbled and the Jaguars recoveredFumble bounces · loose balls are close to 50/50 +37% JAX BUF: Turnover on downs
7 Q4 1:18 The Bills were stopped on 3rd & 73rd & 4th downs · 36% expected +20% JAX BUF: Turnover on downs
8 Q4 1:11 The Bills were stopped on 4th & 163rd & 4th downs · 22% expected +17% JAX –

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.

  • Tre Herndon (JAX CB), out · 0.4 pts
  • A.J. Cann (JAX G), out (IR) · 0.4 pts
  • Brandon Linder (JAX G), out (IR) · 0.4 pts
  • James Robinson (JAX RB), out · 0.2 pts
  • Dawson Knox (BUF TE), out · 0.8 pts
  • Spencer Brown (BUF T), out · 0.7 pts
  • Jon Feliciano (BUF G), out (IR) · 0.3 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

Bills 75% · Jaguars 25%

Final margin
Jaguars by 3
Luck in points
8.2 for the Jaguars
Luck-adjusted margin
Bills by 5.2
Replay with same day's form
Bills 59% · Jaguars 41% 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 9 2021 games · Bills · Jaguars

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