Week 17 2020 · January 3, 2021
No FTN charting for this game (drops and interception-worthy throws are not modelled).
Dolphins at Bills, Week 17 2020: who deserved to win?
The Bills beat the Dolphins 56–26, and the replays back it up: with the way both teams actually played, the Bills win 10 of 10.
An off day for the Dolphins: their offense and defense both played far below their usual level. In a fresh game against the Bills they would win 46% of the time; with this day’s form, 4%. The numbers
Before kickoff the Dolphins were 60% favorites.
Final
 Miami Dolphins | 26 |
|---|---|
 Buffalo Bills | 56 |
Replay with same day's form
Luck index +4 Bills about even · −4 Dolphins
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. Dolphins win 0, Bills win 10.
- 1 MIA 23 BUF 26
- 2 MIA 13 BUF 20
- 3 MIA 21 BUF 32
- 4 MIA 16 BUF 30
- 5 MIA 26 BUF 44
- 6 MIA 16 BUF 37
- 7 MIA 20 BUF 45
- 8 MIA 19 BUF 48
- 9 MIA 23 BUF 59
- 10 MIA 16 BUF 64
Your call
Did the Bills earn it, or get lucky?
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.
An off day for the Dolphins
Their offense and defense both played far below their usual level. In a fresh game against the Bills they would win 46% of the time; with this day’s form, 4%.
Same teams, fresh game
Replay with same day's form
42 points apart for the Dolphins: the gap is how differently this game went from what the two teams usually are.
| Unit | This game | Usual level | Better or worse than usual |
|---|---|---|---|
| Dolphins offenseEPA per play gained | −0.19 | +0.09 | worse by 0.28 |
| Dolphins defenseEPA per play allowed | +0.33 | +0.13 | worse by 0.21 |
| Bills offenseEPA per play gained | +0.33 | +0.18 | better by 0.16 |
| Bills defenseEPA per play allowed | −0.19 | +0.07 | better by 0.26 |
EPA (expected points added) per play on competitive snaps, turnovers left out because they are valued as luck. Usual level: the team’s earlier games this season plus half of last season, pulled toward the league average. One team’s defense and the other team’s offense are the same snaps, so one game can’t fully say whose day it was; it shows how far this one was from both teams’ norms.
How 4,000 replays ended
Dolphins win 4% of them, Bills 96%. The line is what actually happened: Bills by 30.
Show as a table
| Final margin in the replays | Share of replays |
|---|---|
| Dolphins by 17+ | 0.4% |
| Dolphins by 9–16 | 0.8% |
| Dolphins by 1–8 | 2.5% |
| Level after regulation | 0.3% |
| Bills by 1–8 | 6.0% |
| Bills by 9–16 | 14.9% |
| Bills by 17+ | 75.2% |
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.
- J. Sanders, 49 yds made · 71% expected
- J. Sanders, 32 yds made · 95% expected
Penalties: Dolphins 2 for 20 yards, Bills 3 for 16 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 half toward luck; pre-snap fouls, which repeat, don’t count. How calls are valued
| When | Flag | Win probability for |
|---|---|---|
| Q1 5:50 | False Start on the Dolphins (Durham Smythe), 5 yards · pre-snap | +1% BUF +0.8 pts |
| Q2 8:31 | Unnecessary Roughness on the Dolphins (Christian Wilkins), 15 yards | +5% BUF +1.8 pts |
| Q2 3:28 | Defensive Pass Interference on the Bills, 8 yards | 0% MIA +0.6 pts |
| Q3 11:16 | Defensive Pass Interference on the Bills (Josh Norman), 3 yards | +2% MIA +3.2 pts |
| Q4 8:16 | False Start on the Bills (Siran Neal), 5 yards · pre-snap | 0% MIA +0.2 pts |
Dolphins penalties, every game · Bills penalties, every game · All teams, 2020
When it happened
Bills’ chance of winning
As low as 38% and as high as 100%. Numbers mark the biggest luck moments, listed below.
| # | When | What happened | Win probability for | Next drive |
|---|---|---|---|---|
| 1 | Q1 12:13 | The Bills converted 3rd & 43rd & 4th downs · 50% expected | +3% BUF | BUF: Turnover |
| 2 | Q1 8:56 | The Dolphins were stopped on 3rd & 53rd & 4th downs · 40% expected | +5% BUF | MIA: Field goal |
| 3 | Q1 8:12 | J. Sanders made a 49-yard field goalKicks · 71% expected for him, 22 of 31 from 45+ before | +5% MIA | MIA: Punt |
| 4 | Q1 2:56 | The Bills were stopped on 3rd & 43rd & 4th downs · 50% expected | +5% MIA | BUF: Punt |
| 5 | Q2 12:14 | The Bills converted 3rd & 43rd & 4th downs · 42% expected | +4% BUF | BUF: Touchdown |
| 6 | Q2 8:31 | Unnecessary Roughness on the Dolphins (Christian Wilkins), 15 yardsJudgment calls · 3 flags in 1613 snaps before, position avg 1 per 262 | +5% BUF | BUF: Touchdown |
| 7 | Q2 7:05 | The Bills converted 3rd & 43rd & 4th downs · 50% expected | +3% BUF | BUF: Touchdown |
| 8 | Q3 8:28 | Return touchdown by the BillsSpecial teams | +4% BUF | BUF: Opp 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.
- Tre'Davious White (BUF CB), out · 1.3 pts
- Jerry Hughes (BUF DE), out · 0.6 pts
- Cole Beasley (BUF WR), out · 0.5 pts
- Mario Addison (BUF DE), out · 0.4 pts
- Elandon Roberts (MIA LB), out (IR) · 0.3 pts
- Solomon Kindley (MIA G), out · 0.2 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
Dolphins 0% · Bills 100%
- Final margin
- Bills by 30
- Luck in points
- 1.9 for the Dolphins
- Luck-adjusted margin
- Bills by 31.9
- Replay with same day's form
- Dolphins 4% · Bills 96% 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 2020 games · 
Dolphins · 
Bills
More from Week 17 2020
- Falcons at Buccaneers TB 44–27 · replay 98% for the winner
- Ravens at Bengals BAL 38–3 · replay 96% for the winner
- Cowboys at Giants NYG 23–19 · replay 50% for the winner
- Vikings at Lions MIN 37–35 · replay 45% for the winner
- Jets at Patriots NE 28–14 · replay 57% for the winner
- Steelers at Browns CLE 24–22 · replay 71% for the winner
- Cardinals at Rams LA 18–7 · replay 47% for the winner
- Packers at Bears GB 35–16 · replay 94% for the winner
- Jaguars at Colts IND 28–14 · replay 97% for the winner
- Chargers at Chiefs LAC 38–21 · replay 76% for the winner
- Raiders at Broncos LV 32–31 · replay 69% for the winner
- Saints at Panthers NO 33–7 · replay 87% for the winner
- Seahawks vs 49ers SEA 26–23 · replay 78% for the winner
- Titans at Texans TEN 41–38 · replay 40% for the winner
- Washington at Eagles WAS 20–14 · replay 62% for the winner