luckadjusted

Week 14 2021 · December 9, 2021

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

Steelers at Vikings, Week 14 2021: who deserved to win?

The Vikings beat the Steelers 36–28, and it was no fluke: replayed with the way both teams actually played, the Vikings win 8 of 10. The Steelers had the bounces: judgment calls alone were worth 9 points of win probability to the Steelers.

Before kickoff the Vikings were 60% favorites. The biggest swing (Q1, 5:36 left): C. Boswell missed 49-yard field goal, worth 10 points of win probability to the Vikings.

Final

Pittsburgh Steelers 28
Minnesota Vikings 36

December 9, 2021 · U.S. Bank Stadium · Closing line: Vikings −3.5

Luck index +15 Vikings about even · −15 Steelers

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. Steelers win 2, Vikings win 8.

  1. 1 PIT 24 MIN 10
  2. 2 PIT 38 MIN 34
  3. 3 PIT 20 MIN 23
  4. 4 PIT 17 MIN 23
  5. 5 PIT 24 MIN 33
  6. 6 PIT 30 MIN 42
  7. 7 PIT 14 MIN 30
  8. 8 PIT 25 MIN 45
  9. 9 PIT 28 MIN 52
  10. 10 PIT 20 MIN 55

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

Steelers win 15% of them, Vikings 85%, counting the 2% still level after regulation as half each. The line is what actually happened: Vikings by 8.

Show as a table
Final margin in the replaysShare of replays
Steelers by 17+1.8%
Steelers by 9–164.4%
Steelers by 1–88.9%
Level after regulation1.8%
Vikings by 1–817.6%
Vikings by 9–1622.6%
Vikings by 17+42.8%

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 +7.2 points to the Steelers: the final margin was Vikings by 8, without the luck Vikings by 15.2. 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.

  • G. Joseph, 53 yds missed · 70% expected
  • C. Boswell, 49 yds missed · 82% expected
  • G. Joseph, 38 yds made · 91% expected
  • G. Joseph, 42 yds made · 86% expected
  • G. Joseph, 25 yds made · 98% expected
  • Extra point missed · 95% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Steelers 10 for 85 yards, Vikings 11 for 102 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 12:28 Delay of Game on the Vikings, 5 yards · pre-snap +7% PIT +0.9 pts
Q1 9:41 Unnecessary Roughness on the Steelers (Chase Claypool), 15 yards +4% MIN +1.0 pts
Q1 8:13 Defensive Holding on the Vikings (Mackensie Alexander), 5 yards +3% PIT +1.1 pts
Q2 13:11 Offensive Holding on the Vikings (Josh Metellus), 10 yards +2% PIT +0.9 pts
Q2 11:43 Offensive Holding on the Vikings, 10 yards, wiping out the play +3% PIT +1.3 pts
Q2 9:55 Unnecessary Roughness on the Vikings, 15 yards +2% PIT +1.4 pts
Q2 9:55 Illegal Double-Team Block on the Steelers (Benny Snell Jr.), 15 yards +1% MIN +1.1 pts
Q2 2:20 Horse Collar Tackle on the Vikings (Xavier Woods), 15 yards +1% PIT +1.5 pts
Q2 2:00 Offensive Holding on the Steelers (Diontae Johnson), 10 yards 0% MIN +0.6 pts
Q2 0:21 False Start on the Steelers, 5 yards · pre-snap +1% MIN +0.4 pts
Q3 15:00 Offensive Holding on the Steelers (Miles Killebrew), 10 yards +1% MIN +0.8 pts
Q3 14:09 Defensive Offside on the Vikings (D.J. Wonnum), 5 yards · pre-snap 0% MIN +0.9 pts
Q3 13:39 False Start on the Steelers, 5 yards · pre-snap 0% MIN +1.0 pts
Q3 7:07 Unnecessary Roughness on the Steelers (Minkah Fitzpatrick), 5 yards 0% MIN +0.7 pts
Q3 4:04 Ineligible Downfield Pass on the Steelers, 5 yards, wiping out the play 0% MIN +1.8 pts
Q3 3:44 Taunting on the Vikings (Kris Boyd), 15 yards 0% PIT +1.4 pts
Q3 0:52 Neutral Zone Infraction on the Vikings (Mackensie Alexander), 5 yards · pre-snap 0% PIT +0.9 pts
Q4 14:55 Defensive Pass Interference on the Vikings (Cameron Dantzler), 7 yards 0% PIT +3.1 pts
Q4 9:03 Delay of Game on the Steelers, 5 yards · pre-snap +1% MIN +0.5 pts
Q4 3:39 Offensive Holding on the Vikings, 10 yards, wiping out the play +3% PIT +1.4 pts
Q4 2:05 Illegal Block Above the Waist on the Steelers, 10 yards +1% MIN +0.9 pts

Steelers penalties, every game · Vikings penalties, every game · All teams, 2021

When it happened

Vikings’ chance of winning

As low as 39% 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 Vikings were ahead in it, below while the Steelers were.
#WhenWhat happenedWin probability forNext drive
1 Q1 12:28 The Vikings were stopped on 3rd & 113rd & 4th downs · 27% expectedDelay of Game on the Vikings, 5 yardsPre-snap flags +4% PIT MIN: Missed field goal
2 Q1 11:47 G. Joseph missed 53-yard field goalKicks · 70% expected for him, 8 of 11 from 45+ before +8% PIT MIN: Touchdown
3 Q1 10:22 The Steelers converted 3rd & 13rd & 4th downs · 73% expected +3% PIT PIT: Missed field goal
4 Q1 9:41 Unnecessary Roughness on the Steelers (Chase Claypool), 15 yardsJudgment calls · 8 flags in 1446 snaps before, position avg 1 per 399 +4% MIN MIN: Touchdown
5 Q1 6:58 The Steelers fumbled and recovered it themselvesFumble bounces · loose balls are close to 50/50 +4% PIT PIT: Missed field goal
6 Q1 5:36 C. Boswell missed 49-yard field goalKicks · 82% expected for him, 20 of 22 from 45+ before +10% MIN PIT: Punt
7 Q2 14:47 G. Joseph made 38-yard field goalKicks · 91% expected for him +3% MIN MIN: Touchdown
8 Q4 3:39 Offensive Holding on the Vikings, 10 yards, wiping out the playJudgment calls +3% PIT PIT: End of game

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.

  • Danielle Hunter (MIN DE), out (IR) · 1.2 pts
  • Everson Griffen (MIN DE), out (IR) · 0.9 pts
  • Christian Darrisaw (MIN T), out · 0.8 pts
  • Adam Thielen (MIN WR), out · 0.7 pts
  • Joe Haden (PIT CB), out · 1.1 pts
  • Kevin Dotson (PIT G), 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

Steelers 3% · Vikings 97%

Final margin
Vikings by 8
Luck in points
7.2 for the Steelers
Luck-adjusted margin
Vikings by 15.2
Replay with same day's form
Steelers 15% · Vikings 85% 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 14 2021 games · Steelers · Vikings

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