luckadjusted

Week 2 2021 · September 19, 2021

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

Broncos at Jaguars, Week 2 2021: who deserved to win?

The Broncos beat the Jaguars 23–13, and it was no fluke: replayed with the way both teams actually played, the Broncos win 9 of 10. The Jaguars had the bounces: judgment calls alone were worth 9 points of win probability to the Jaguars.

Before kickoff the Broncos were 67% favorites. The biggest swing (Q2, 0:46 left): the Jaguars converted 4th & 5, worth 10 points of win probability to the Jaguars.

Final

Denver Broncos 23
Jacksonville Jaguars 13

September 19, 2021 · TIAA Bank Stadium · Closing line: Broncos −6

Luck index +12 Broncos about even · −12 Jaguars

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, Jaguars win 1.

  1. 1 DEN 38 JAX 7
  2. 2 DEN 38 JAX 15
  3. 3 DEN 24 JAX 6
  4. 4 DEN 20 JAX 6
  5. 5 DEN 25 JAX 14
  6. 6 DEN 23 JAX 15
  7. 7 DEN 19 JAX 13
  8. 8 DEN 17 JAX 13
  9. 9 DEN 15 JAX 13
  10. 10 DEN 7 JAX 13

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 88% of them, Jaguars 12%, counting the 2% still level after regulation as half each. The line is what actually happened: Broncos by 10.

Show as a table
Final margin in the replaysShare of replays
Broncos by 17+42.1%
Broncos by 9–1624.8%
Broncos by 1–820.3%
Level after regulation1.8%
Jaguars by 1–87.1%
Jaguars by 9–163.0%
Jaguars by 17+0.8%

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 +2.8 points to the Broncos: the final margin was Broncos by 10, without the luck Broncos by 7.2. 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.

  • B. McManus, 32 yds made · 96% expected
  • J. Lambo, 52 yds missed · 70% expected
  • J. Lambo, 48 yds missed · 76% expected
  • B. McManus, 46 yds made · 80% expected
  • B. McManus, 40 yds made · 88% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Broncos 10 for 101 yards, Jaguars 7 for 70 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 toward luck, pre-snap fouls mostly don’t. How calls are valued

WhenFlagWin probability for
Q1 12:27 Illegal Contact on the Broncos (Kyle Fuller), 5 yards +4% JAX +1.3 pts
Q1 9:51 False Start on the Jaguars (Laviska Shenault Jr.), 5 yards · pre-snap +2% DEN +0.7 pts
Q1 8:01 Defensive Holding on the Jaguars (Shaquill Griffin), 5 yards +4% DEN +1.7 pts
Q2 11:47 Unsportsmanlike Conduct on the Broncos, 15 yards +3% JAX +1.4 pts
Q2 11:47 False Start on the Broncos (Baron Browning), 5 yards · pre-snap +1% JAX +0.4 pts
Q2 10:15 Defensive Pass Interference on the Broncos (Patrick Surtain II), 36 yards +6% JAX +2.8 pts
Q2 1:04 Defensive Offside on the Broncos (Bradley Chubb), 5 yards · pre-snap +2% JAX +0.2 pts
Q3 7:04 False Start on the Broncos (Nate Hairston), 5 yards · pre-snap +2% JAX +0.4 pts
Q3 6:08 Neutral Zone Infraction on the Broncos (Von Miller), 5 yards · pre-snap +1% JAX +0.4 pts
Q3 1:04 Offensive Holding on the Jaguars, 10 yards +1% DEN +1.1 pts
Q3 1:00 Encroachment on the Broncos (Dre'Mont Jones), 5 yards · pre-snap +1% JAX +0.4 pts
Q4 12:00 Roughing the Passer on the Broncos (Dre'Mont Jones), 15 yards +3% JAX +2.4 pts
Q4 12:00 False Start on the Jaguars (Tyron Johnson), 5 yards · pre-snap +1% DEN +0.5 pts
Q4 10:39 False Start on the Jaguars, 5 yards · pre-snap +2% DEN +0.5 pts
Q4 9:06 Defensive Pass Interference on the Jaguars (Rayshawn Jenkins), 35 yards +1% DEN +2.4 pts
Q4 6:40 False Start on the Broncos (Noah Fant), 5 yards · pre-snap 0% JAX +0.5 pts
Q4 5:26 Delay of Game on the Jaguars, 5 yards · pre-snap 0% DEN 0.0 pts

Broncos penalties, every game · Jaguars penalties, every game · All teams, 2021

When it happened

Jaguars’ chance of winning

As low as 0% and as high as 74%. 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 Broncos were.
#WhenWhat happenedWin probability forNext drive
1 Q1 11:46 The Jaguars converted 3rd & 33rd & 4th downs · 48% expected +5% JAX JAX: Touchdown
2 Q1 9:27 The Jaguars converted 3rd & 133rd & 4th downs · 21% expected +9% JAX JAX: Touchdown
3 Q2 10:15 Defensive Pass Interference on the Broncos (Patrick Surtain II), 36 yardsJudgment calls · 0 flags in 17 snaps before, position avg 1 per 213 +6% JAX JAX: Missed field goal
4 Q2 4:26 The Broncos converted 3rd & 63rd & 4th downs · 39% expected +6% DEN DEN: Touchdown
5 Q2 0:50 The Jaguars were stopped on 3rd & 53rd & 4th downs · 37% expected +6% DEN JAX: Missed field goal
6 Q2 0:46 The Jaguars converted 4th & 53rd & 4th downs · 37% expected +10% JAX JAX: Missed field goal
7 Q2 0:30 The Jaguars were stopped on 3rd & 103rd & 4th downs · 25% expected +7% DEN JAX: Missed field goal
8 Q2 0:24 J. Lambo missed 48-yard field goalKicks · 76% expected for him, 9 of 12 from 45+ before +7% DEN JAX: 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.

  • Tre Herndon (JAX CB), out · 0.6 pts
  • Jerry Jeudy (DEN WR), out (IR) · 0.7 pts
  • Graham Glasgow (DEN G), out · 0.4 pts
  • Michael Ojemudia (DEN CB), 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 81% · Jaguars 19%

Final margin
Broncos by 10
Luck in points
2.8 for the Broncos
Luck-adjusted margin
Broncos by 7.2
Replay with same day's form
Broncos 88% · Jaguars 12% 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 2 2021 games · Broncos · Jaguars

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