luckadjusted

Week 15 2021 · December 19, 2021

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

Titans at Steelers, Week 15 2021: who deserved to win?

The Steelers beat the Titans 19–13 and were the better team on the day: replayed with the same form, they win 7 of 10.

Before kickoff it was a pick’em. The game turned on a luck play (Q4, 14:57 left): Roughing the Passer on the Titans (Jeffery Simmons), 14 yards, wiping out the play, worth 17 points of win probability to the Steelers. The biggest single swing (Q4, 0:46 left): the Titans were stopped on 4th & 7.

Final

Tennessee Titans 13
Pittsburgh Steelers 19

December 19, 2021 · Heinz Field · Closing line: Steelers −1

Luck index +33 Steelers lucky · −33 Titans

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. Titans win 3, Steelers win 7.

  1. 1 TEN 26 PIT 6
  2. 2 TEN 20 PIT 12
  3. 3 TEN 20 PIT 17
  4. 4 TEN 20 PIT 22
  5. 5 TEN 13 PIT 17
  6. 6 TEN 10 PIT 16
  7. 7 TEN 3 PIT 13
  8. 8 TEN 7 PIT 21
  9. 9 TEN 14 PIT 31
  10. 10 TEN 10 PIT 37

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

Titans win 33% of them, Steelers 67%, counting the 2% still level after regulation as half each. The line is what actually happened: Steelers by 6.

Show as a table
Final margin in the replaysShare of replays
Titans by 17+5.3%
Titans by 9–169.5%
Titans by 1–817.9%
Level after regulation2.3%
Steelers by 1–828.1%
Steelers by 9–1619.6%
Steelers by 17+17.3%

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 +9.7 points to the Steelers: the final margin was Steelers by 6, without the luck Titans by 3.7. 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.

  • R. Bullock, 26 yds made · 97% expected
  • C. Boswell, 36 yds made · 91% expected
  • R. Bullock, 32 yds made · 93% expected
  • C. Boswell, 56 yds missed · 59% expected
  • C. Boswell, 28 yds made · 98% expected
  • C. Boswell, 46 yds made · 77% expected
  • C. Boswell, 48 yds made · 73% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Titans 7 for 68 yards, Steelers 5 for 30 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 10:29 Illegal Block Above the Waist on the Steelers, 10 yards +3% TEN +0.9 pts
Q1 5:44 Encroachment on the Steelers (Cameron Heyward), 5 yards · pre-snap +1% TEN +0.6 pts
Q2 15:00 False Start on the Steelers, 5 yards · pre-snap +2% TEN +1.2 pts
Q2 12:17 False Start on the Steelers, 5 yards · pre-snap +2% TEN +0.9 pts
Q2 3:24 Offensive Holding on the Titans, 10 yards +3% PIT +1.2 pts
Q2 1:14 False Start on the Titans, 5 yards · pre-snap +1% PIT +1.0 pts
Q3 10:55 Defensive Offside on the Titans, 5 yards, wiping out the play · pre-snap +12% PIT +4.1 pts
Q3 6:06 Unnecessary Roughness on the Titans (Kristian Fulton), 15 yards +4% PIT +1.9 pts
Q3 4:30 Defensive Pass Interference on the Titans (Kristian Fulton), 9 yards +1% PIT +1.4 pts
Q4 14:57 Roughing the Passer on the Titans (Jeffery Simmons), 14 yards, wiping out the play +17% PIT +3.6 pts
Q4 14:05 False Start on the Steelers (Diontae Johnson), 5 yards · pre-snap +7% TEN +0.4 pts
Q4 12:56 Offensive Holding on the Titans, 10 yards +4% PIT +0.9 pts

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

When it happened

Steelers’ chance of winning

As low as 14% 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 Steelers were ahead in it, below while the Titans were.
#WhenWhat happenedWin probability forNext drive
1 Q3 10:55 Defensive Offside on the Titans, 5 yards, wiping out the playPre-snap flags +12% PIT PIT: Punt
2 Q3 0:57 The Titans were stopped on 3rd & 63rd & 4th downs · 37% expectedThe Titans fumbled and the Steelers recoveredFumble bounces · loose balls are close to 50/50 +22% PIT TEN: Turnover
3 Q4 14:57 The game turned hereRoughing the Passer on the Titans (Jeffery Simmons), 14 yards, wiping out the playJudgment calls · 7 flags in 2262 snaps before, position avg 1 per 273 +17% PIT PIT: Field goal
4 Q4 11:29 The Titans converted 3rd & 113rd & 4th downs · 26% expected +11% TEN TEN: Turnover
5 Q4 9:24 The Titans were stopped on 3rd & 33rd & 4th downs · 51% expected +16% PIT TEN: Turnover
6 Q4 6:41 The Titans fumbled and the Steelers recoveredFumble bounces · loose balls are close to 50/50 +10% PIT TEN: Turnover on downs
7 Q4 0:59 The Titans fumbled and recovered it themselvesFumble bounces · loose balls are close to 50/50 +24% TEN TEN: Turnover on downs
8 Q4 0:46 The Titans were stopped on 4th & 73rd & 4th downs · 33% expected +24% PIT –

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.

  • Kevin Dotson (PIT G), out (IR) · 0.4 pts
  • Montravius Adams (PIT DE), out (IR) · 0.2 pts
  • A.J. Brown (TEN WR), out (IR) · 1.4 pts
  • Derrick Henry (TEN RB), out (IR) · 0.5 pts
  • Rodger Saffold (TEN G), out · 0.5 pts
  • David Long (TEN LB), out · 0.4 pts
  • Monty Rice (TEN LB), out (IR) · 0.1 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

Titans 54% · Steelers 46%

Final margin
Steelers by 6
Luck in points
9.7 for the Steelers
Luck-adjusted margin
Titans by 3.7
Replay with same day's form
Titans 33% · Steelers 67% 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 15 2021 games · Titans · Steelers

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