luckadjusted

Week 1 2020 · September 13, 2020

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

Seahawks at Falcons, Week 1 2020: who deserved to win?

The Seahawks beat the Falcons 38–25, but the Falcons played well enough to win it: they take 7 of 10 replays with the same day's form. Luck ran their way: judgment calls alone were worth 11 points of win probability to the Seahawks.

Before kickoff it was a pick’em. The game turned on a luck play (Q1, 5:04 left): Defensive Pass Interference on the Falcons (Ricardo Allen), 41 yards, worth 15 points of win probability to the Seahawks. The biggest single swing (Q3, 9:49 left): the Seahawks converted 4th & 5.

Final

Seattle Seahawks 38
Atlanta Falcons 25

September 13, 2020 · Mercedes-Benz Stadium · Closing line: Falcons −1

Luck index +66 Seahawks very lucky · −66 Falcons

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. Seahawks win 3, Falcons win 7.

  1. 1 SEA 27 ATL 9
  2. 2 SEA 32 ATL 23
  3. 3 SEA 16 ATL 13
  4. 4 SEA 24 ATL 27
  5. 5 SEA 33 ATL 38
  6. 6 SEA 31 ATL 40
  7. 7 SEA 32 ATL 44
  8. 8 SEA 29 ATL 45
  9. 9 SEA 14 ATL 37
  10. 10 SEA 10 ATL 41

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

Seahawks win 34% of them, Falcons 66%, counting the 3% still level after regulation as half each. The line is what actually happened: Seahawks by 13.

Show as a table
Final margin in the replaysShare of replays
Seahawks by 17+5.7%
Seahawks by 9–169.5%
Seahawks by 1–815.4%
Level after regulation3.4%
Falcons by 1–822.9%
Falcons by 9–1619.5%
Falcons by 17+23.5%

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 +8.2 points to the Seahawks: the final margin was Seahawks by 13, without the luck Seahawks by 4.8. 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.

  • Y. Koo, 49 yds made · 77% expected
  • Y. Koo, 49 yds made · 77% expected
  • J. Myers, 42 yds made · 86% expected
  • Extra point missed · 89% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Seahawks 6 for 46 yards, Falcons 6 for 72 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 11:59 Intentional Grounding on the Falcons (Matt Ryan), 11 yards +3% SEA +1.1 pts
Q1 6:13 Offensive Holding on the Seahawks, 10 yards +5% ATL +1.8 pts
Q1 5:04 Defensive Pass Interference on the Falcons (Ricardo Allen), 41 yards +15% SEA +5.2 pts
Q2 11:25 False Start on the Falcons, 5 yards · pre-snap 0% SEA 0.0 pts
Q2 4:00 False Start on the Falcons (Calvin Ridley), 5 yards · pre-snap +2% SEA +0.6 pts
Q2 2:00 False Start on the Seahawks, 5 yards · pre-snap +2% ATL +0.5 pts
Q2 0:57 Illegal Formation on the Falcons (Christian Blake), 5 yards · pre-snap +4% SEA +0.7 pts
Q2 0:50 Defensive Pass Interference on the Seahawks (Shaquill Griffin), 11 yards +3% ATL +0.8 pts
Q3 11:49 Defensive Too Many Men on Field on the Falcons, 5 yards · pre-snap 0% SEA +0.3 pts
Q4 13:03 Offensive Holding on the Seahawks, 10 yards, wiping out the play +1% ATL +1.3 pts
Q4 13:03 False Start on the Seahawks, 5 yards · pre-snap 0% ATL +0.8 pts
Q4 13:03 False Start on the Seahawks (Greg Olsen), 5 yards · pre-snap 0% ATL +0.7 pts

Seahawks penalties, every game · Falcons penalties, every game · All teams, 2020

When it happened

Falcons’ chance of winning

As low as 0% and as high as 64%. 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 Falcons were ahead in it, below while the Seahawks were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:05 The Falcons converted 3rd & 113rd & 4th downs · 28% expected +11% ATL ATL: Field goal
2 Q1 5:04 The game turned hereDefensive Pass Interference on the Falcons (Ricardo Allen), 41 yardsJudgment calls · 2 flags in 955 snaps before, position avg 1 per 237 +15% SEA SEA: Touchdown
3 Q1 2:54 The Falcons were stopped on 3rd & 13rd & 4th downs · 76% expected +8% SEA ATL: Turnover on downs
4 Q1 2:14 The Falcons were stopped on 4th & 33rd & 4th downs · 54% expected +7% SEA ATL: Touchdown
5 Q2 0:17 The Falcons converted 3rd & 103rd & 4th downs · 29% expected +8% ATL ATL: Field goal
6 Q2 0:02 Y. Koo made 49-yard field goalKicks · 77% expected for him, 5 of 5 from 45+ before +7% ATL ATL: Turnover
7 Q3 9:49 The Seahawks converted 4th & 53rd & 4th downs · 42% expected +18% SEA SEA: Touchdown
8 Q3 7:59 The Falcons were stopped on 4th & 23rd & 4th downs · 62% expectedThe Falcons fumbled and the Seahawks recoveredFumble bounces · loose balls are close to 50/50 +9% SEA ATL: Turnover on downs

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.

  • Kendall Sheffield (ATL CB), 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

Seahawks 73% · Falcons 27%

Final margin
Seahawks by 13
Luck in points
8.2 for the Seahawks
Luck-adjusted margin
Seahawks by 4.8
Replay with same day's form
Seahawks 34% · Falcons 66% 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 2020 games · Seahawks · Falcons

More from Week 1 2020