Week 17 2019 · December 29, 2019
No FTN charting for this game (drops and interception-worthy throws are not modelled).
49ers at Seahawks, Week 17 2019: who deserved to win?
The 49ers beat the Seahawks 26–21 and were the better team on the day: replayed with the same form, they win 7 of 10.
Before kickoff the 49ers were 60% favorites. The biggest swing (Q4, 0:12 left): the Seahawks were stopped on 4th & 5, worth 28 points of win probability to the 49ers.
Final
 San Francisco 49ers | 26 |
|---|---|
 Seattle Seahawks | 21 |
Replay with same day's form
Luck index +28 49ers lucky · −28 Seahawks
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. 49ers win 7, Seahawks win 3.
- 1 SF 37 SEA 13
- 2 SF 27 SEA 10
- 3 SF 34 SEA 20
- 4 SF 27 SEA 16
- 5 SF 13 SEA 6
- 6 SF 31 SEA 27
- 7 SF 30 SEA 28
- 8 SF 31 SEA 34
- 9 SF 3 SEA 10
- 10 SF 20 SEA 34
Three other ways to ask
Each answers a different question, so none of them replaces the replay above.
Before kickoff
The closing betting line, turned into a probability. What everyone knew before the game.
Same teams, fresh 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.
Only coin-flips re-rolled
Every kick, fumble bounce, drop, conversion and judgment call redrawn; everything else fixed. The narrowest view of luck.
How 4,000 replays ended
49ers win 72% of them, Seahawks 28%, counting the 5% still level after regulation as half each. The line is what actually happened: 49ers by 5.
Show as a table
| Final margin in the replays | Share of replays |
|---|---|
| 49ers by 17+ | 21.6% |
| 49ers by 9–16 | 22.1% |
| 49ers by 1–8 | 27.3% |
| Level after regulation | 5.0% |
| Seahawks by 1–8 | 14.8% |
| Seahawks by 9–16 | 6.7% |
| Seahawks by 17+ | 2.7% |
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.
The kicks
How likely each kicker was to make that kick (his own record, the distance and the weather), and what happened.
- R. Gould, 47 yds made · 73% expected
- R. Gould, 30 yds made · 95% expected
Penalties: 49ers 8 for 57 yards, Seahawks 5 for 29 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
| When | Flag | Win probability for |
|---|---|---|
| Q1 15:00 | Defensive Holding on the 49ers (Dre Greenlaw), 5 yards | +1% SEA +0.3 pts |
| Q1 12:21 | Neutral Zone Infraction on the Seahawks (Jadeveon Clowney), 5 yards · pre-snap | +1% SF +0.5 pts |
| Q2 11:38 | Offensive Holding on the 49ers (D.J. Reed), 10 yards | +2% SEA +0.7 pts |
| Q2 8:05 | Illegal Shift on the 49ers, 5 yards · pre-snap | +2% SEA +1.1 pts |
| Q2 6:00 | Delay of Game on the 49ers, 5 yards · pre-snap | +2% SEA +0.2 pts |
| Q2 4:24 | Neutral Zone Infraction on the 49ers (Nick Bosa), 5 yards · pre-snap | +2% SEA +1.2 pts |
| Q2 1:56 | False Start on the Seahawks (Travis Homer), 5 yards · pre-snap | +1% SF +0.6 pts |
| Q2 1:15 | False Start on the Seahawks, 5 yards · pre-snap | +2% SF +0.6 pts |
| Q3 9:21 | Offensive Holding on the Seahawks, 10 yards, wiping out the play | +11% SF +3.7 pts |
| Q4 10:04 | Defensive Holding on the 49ers (Marcell Harris), 0 yards | 0% SEA 0.0 pts |
| Q4 4:22 | Defensive Pass Interference on the 49ers, 14 yards | +2% SEA +1.8 pts |
| Q4 2:52 | Unnecessary Roughness on the 49ers, 13 yards | +5% SEA +1.2 pts |
| Q4 0:22 | Delay of Game on the Seahawks, 4 yards · pre-snap | +9% SF +0.7 pts |
49ers penalties, every game · Seahawks penalties, every game · All teams, 2019
When it happened
Seahawks’ chance of winning
As low as 0% and as high as 60%. Numbers mark the biggest luck moments, listed below.
| # | When | What happened | Win probability for | Next drive |
|---|---|---|---|---|
| 1 | Q1 6:50 | The Seahawks converted 3rd & 83rd & 4th downs · 30% expected | +8% SEA | SEA: Punt |
| 2 | Q3 9:21 | Offensive Holding on the Seahawks, 10 yards, wiping out the playJudgment calls | +11% SF | SF: Touchdown |
| 3 | Q3 5:53 | The Seahawks converted 3rd & 93rd & 4th downs · 28% expected | +9% SEA | SEA: Touchdown |
| 4 | Q4 0:46 | The Seahawks were stopped on 3rd & 103rd & 4th downs · 26% expected | +10% SF | SEA: Turnover on downs |
| 5 | Q4 0:42 | The Seahawks converted 4th & 103rd & 4th downs · 26% expected | +26% SEA | SEA: Turnover on downs |
| 6 | Q4 0:22 | Delay of Game on the Seahawks, 4 yardsPre-snap flags | +9% SF | SF: End of game |
| 7 | Q4 0:15 | The Seahawks were stopped on 3rd & 53rd & 4th downs · 32% expected | +7% SF | SEA: Turnover on downs |
| 8 | Q4 0:12 | The Seahawks were stopped on 4th & 53rd & 4th downs · 32% expected | +28% SF | – |
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.
- Duane Brown (SEA T), out · 1.0 pts
- Quandre Diggs (SEA SS), out · 0.5 pts
- Chris Carson (SEA RB), out (IR) · 0.4 pts
- Weston Richburg (SF C), out (IR) · 0.6 pts
- Jaquiski Tartt (SF SS), 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
49ers 75% · Seahawks 25%
- Final margin
- 49ers by 5
- Luck in points
- 2.0 for the 49ers
- Luck-adjusted margin
- 49ers by 3.0
- Replay with same day's form
- 49ers 72% · Seahawks 28% unchanged: why
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 17 2019 games · 
49ers · 
Seahawks
More from Week 17 2019
- Falcons at Buccaneers ATL 28–22 · replay 14% for the winner
- Bears at Vikings CHI 21–19 · replay 9% for the winner
- Browns at Bengals CIN 33–23 · replay 49% for the winner
- Packers at Lions GB 23–20 · replay 43% for the winner
- Chargers at Chiefs KC 31–21 · replay 80% for the winner
- Dolphins at Patriots MIA 27–24 · replay 43% for the winner
- Saints at Panthers NO 42–10 · replay 95% for the winner
- Jets at Bills NYJ 13–6 · replay 38% for the winner
- Cardinals at Rams LA 31–24 · replay 62% for the winner
- Colts at Jaguars JAX 38–20 · replay 59% for the winner
- Raiders at Broncos DEN 16–15 · replay 13% for the winner
- Eagles at Giants PHI 34–17 · replay 66% for the winner
- Steelers at Ravens BAL 28–10 · replay 96% for the winner
- Titans at Texans TEN 35–14 · replay 87% for the winner
- Washington at Cowboys DAL 47–16 · replay 96% for the winner