luckadjusted

Week 1 2019 · September 8, 2019

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

Chiefs at Jaguars, Week 1 2019: who deserved to win?

The Chiefs beat the Jaguars 40–26, and it was no fluke: replayed with the way both teams actually played, the Chiefs win 9 of 10.

Before kickoff the Chiefs were 60% favorites. The biggest swing (Q3, 8:59 left): the Jaguars were stopped on 3rd & 2, worth 25 points of win probability to the Chiefs.

Final

Kansas City Chiefs 40
Jacksonville Jaguars 26

September 8, 2019 · TIAA Bank Stadium · Closing line: Chiefs −3.5

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

  1. 1 KC 41 JAX 9
  2. 2 KC 38 JAX 14
  3. 3 KC 34 JAX 14
  4. 4 KC 34 JAX 17
  5. 5 KC 41 JAX 26
  6. 6 KC 39 JAX 28
  7. 7 KC 30 JAX 21
  8. 8 KC 33 JAX 27
  9. 9 KC 38 JAX 35
  10. 10 KC 17 JAX 23

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

Chiefs win 91% of them, Jaguars 9%, 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
Chiefs by 17+53.1%
Chiefs by 9–1620.6%
Chiefs by 1–816.9%
Level after regulation1.8%
Jaguars by 1–85.2%
Jaguars by 9–161.7%
Jaguars by 17+0.6%

Where the luck was

Take the luck out

The final margin was Chiefs by 14. Remove the luck, one kind at a time, and it becomes Chiefs by 13.0.

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.

  • H. Butker, 28 yds made · 97% expected
  • J. Lambo, 37 yds made · 91% expected
  • H. Butker, 25 yds made · 98% expected
  • J. Lambo, 23 yds made · 99% expected
  • H. Butker, 46 yds made · 78% expected
  • H. Butker, 35 yds made · 93% 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 0% and as high as 59%. 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 Chiefs were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:36 The Chiefs converted 3rd & 33rd & 4th downs · 55% expected +19% KC KC: Touchdown
2 Q1 11:58 The Jaguars were stopped on 3rd & 43rd & 4th downs · 46% expected +4% KC JAX: Punt
3 Q1 5:31 The Jaguars converted 3rd & 83rd & 4th downs · 32% expected +13% JAX JAX: Touchdown
4 Q2 14:15 Offensive Holding on the Jaguars, 10 yardsJudgment calls +4% KC KC: Field goal
5 Q3 13:13 The Jaguars converted 3rd & 33rd & 4th downs · 53% expected +4% JAX JAX: Turnover
6 Q3 11:22 The Jaguars converted 3rd & 23rd & 4th downs · 61% expected +4% JAX JAX: Turnover
7 Q3 8:59 The Jaguars were stopped on 3rd & 23rd & 4th downs · 61% expectedThe Jaguars fumbled and the Chiefs recoveredFumble bounces · loose balls are close to 50/50 +25% KC JAX: Punt
8 Q3 4:12 Defensive Offside on the Jaguars (Calais Campbell), 5 yards, wiping out the playPre-snap flags · no snap history yet +6% KC KC: Touchdown

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.

  • Marcell Dareus (JAX NT), out · 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

Chiefs 98% · Jaguars 2%

Final margin
Chiefs by 14
Luck in points
1.0 for the Chiefs
Luck-adjusted margin
Chiefs by 13.0
Replay with same day's form
Chiefs 91% · Jaguars 9% 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 1 2019 games · Chiefs · Jaguars

More from Week 1 2019