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1 other measure was inside a third of the league's own spread — two clubs doing the same thing, so it is not shown.
1 of the 3 swings name a man the week's roster cannot confirm, so that portrait is withheld.
Drawn from the weekly play-by-play file, which paints on the Monday 4:00 AM ET sync after the game.
The model against the market, the momentum underneath, every drive — scrub to replay it
How the game was won
The model and the market were 1.4 win-probability points apart on the average play, and 8 apart at the widest — with the model the more convinced about 49ers.
MarketModelmodel higher on 49ershigher on Bills164 of 173 plays carry both curves
(1:34) 17-J.Allen FUMBLES (Aborted) at BUF 0, RECOVERED by SF-54-F.Warner at BUF 3.
Swing +11.9 for 49ersExpected points +5.49 for 49ersModel and market agree here.play 29
The solid line is the betting market's home win probability; the dashed line is the play-by-play model's. The shaded band between them is the disagreement — emerald where the model liked the home team more, red where it liked the away team more. Drag across the curve or use arrow keys to replay the game; gold diamonds mark the biggest swings.
Highest-leverage plays
1st · 1:34BUF +12% win prob(1:34) 17-J.Allen FUMBLES (Aborted) at BUF 0, RECOVERED by SF-54-F.Warner at BUF 3.
2nd · 13:06SF +10% win prob(13:06) (Shotgun) 17-J.Allen pass short right to 11-C.Beasley for 5 yards, TOUCHDOWN.
1st · 9:23BUF +7% win prob(9:23) 17-J.Allen pass incomplete short middle to 85-L.Smith.
2nd · 3:16SF +7% win prob(3:16) 26-D.Singletary left end pushed ob at SF 4 for 1 yard (33-T.Moore; 20-J.Ward).
1st · 1:38BUF +7% win prob(1:38) (Shotgun) 30-J.Wilson up the middle to BUF 1 for no gain (49-T.Edmunds, 94-V.Butler).
1st · 7:57SF +6% win prob(7:57) (Shotgun) 4-N.Mullens pass incomplete deep right to 11-B.Aiyuk (39-L.Wallace). PENALTY on BUF-39-L.Wallace, Defensive Pass Interference, 25 yards, enforced at SF 5 - No Play.
3rd · 5:44
SettledThe modelled figures are the league play-by-play model's, not ours.
How the points landed
The margin ledger
Dawson Knox's 4-yard touchdown catch with 2:47 left in the 2nd put Buffalo Bills ahead for good. The lead never changed over the 7 scores that followed.
Lead
1st0:48Brandon Aiyuk·2-yd TD catch2-yard touchdown catchfrom Nick Mullensfrom Nick Mullens+70–7
4th0:50Jordan Reed·5-yd TD catch5-yard touchdown catchfrom Nick Mullensfrom Nick Mullens+734–24
10 scores · bar length is the lead after each one
Down-to-down truth
Situational splits
Billscategory by category49ers
Bills4–449ers
450Total yards402
6.7Yards per play6.7
61%Success rate50%
44%Third-down rate55%
2Red-zone touchdowns3
7Explosive plays8
28First downs23
1Sacks taken0
2Turnovers2
The read
Deadlocked at 4–4 categories. Biggest gap to 49ers, in sacks taken.
Expected points added, per play
The centre line is an average play. A bar to the right of it is a side that gained more than the situation was worth; a bar to the left is a side that lost ground. All six bars share one scale, ±0.53 points.
Every snapexpected points added per play, all downs
+0.21Bills: +0.21 expected points added per play
+0.0949ers: +0.09 expected points added per play
Dropping backexpected points added per dropback
+0.53Bills: +0.53 expected points added per play
+0.2849ers: +0.28 expected points added per play
Running itexpected points added per rush
−0.38Bills: −0.38 expected points added per play
−0.2849ers: −0.28 expected points added per play
Neither side “wins” volume or play-calling mix, so neither is drawn as a duel: Bills ran 67 snaps at a 64% dropback rate against 49ers’s 60 at 65%. Red-zone trips: Bills 7, 49ers 5.
NoteBills won the down-to-down efficiency fight: 0.21 expected points added per play vs 0.09.
Derived from the play-by-play, no model
The Read
7 of 8 readings cleared their snap floor and were tested against four comparisons: this week's whole slate, the team's own season, the week before, and the team's own ordinary spread. Every bar below is set in that team's own week-to-week swing, never in league points — one team's swing runs 1.6 to 3.1 times the entire league's spread.
high through week 13Against their seasonFourth Down
BUF's fourth-and-short go rate, 100.0%, is past their previous high of 25.0% in week 1 — the highest of their 5 charted games through week 13.
3 fourth-and-short calls this game, floor 3 — 7 of their games behind the ruler, and their own week-to-week swing is 39.4 points.
BUF's pass rate over expected turned over: −2.8 pts in week 12 against +17.8 pts here — they ran more than the situation asked then and threw more than the situation asked now, a turn of 2.1 of their own weekly swings across the two.
67 snaps this game, floor 20 — 16 of their games behind the ruler, and their own week-to-week swing is 9.6 points.
BUF's early-down pass rate turned over: 47.9% in week 12 against 67.3% here — they ran early then and passed early now, a turn of 2.1 of their own weekly swings across the two.
55 early downs this game, floor 15 — 16 of their games behind the ruler, and their own week-to-week swing is 9.4 points.
SF's pass rate over expected turned over: −12.1 pts in week 12 against −4.6 pts here — they ran more than the situation asked then and threw more than the situation asked now, a turn of 2.2 of their own weekly swings across the two.
60 snaps this game, floor 20 — 16 of their games behind the ruler, and their own week-to-week swing is 3.4 points.
The season-grain rooms, pointed at this one game
Was this normal for them?
7 of 8 readings cleared their snap floor. Every deviation below is measured in that team's own game-to-game swing, not in league points — because one game's swing runs from 1.6 to 3.1 times the whole league's spread.
their week-to-week swingall 32 teams
upper band = their week-to-week swing · lower rule = all 32 teams · scale -16 pts to 33 pts
inside their normal wobble · +3.3 vs their 14.6%, and they swing ±6.0 week to week (+0.56× that swing) · 39 dropbacks
49ers7.0%
inside their normal wobble · −5.1 vs their 12.1%, and they swing ±6.7 week to week (−0.77× that swing) · 43 dropbacks
Play-action rate
Charted from 2022. The columns exist for 2020 and are entirely empty, which is not a season of data.
Blitz rate sent
Charted from 2022. The columns exist for 2020 and are entirely empty, which is not a season of data.
NoteBUF's fourth-and-short go rate was the night's one real departure: 100.0%, 73.6 points above their season mean of 26.4% and 1.9 times their own 39.4-point weekly swing.
The Game Day Roster
Who was out, who dressed and never took a snap, and who was on the field how much. Game-day list and snap counts from the weekly roster and snap feeds. Practice-squad and injured-reserve players are not shown — they were never on the game-day list.
Snap, route and expected-points data starts in 2021. This game is older than the usage record, so there is no opportunity read for it — the box score above is the complete picture we hold.
The field map
Every snap, where it happened
The whole game as one hundred yards. The 49ers attack right, the Bills attack left, so a change of possession is a reversal you can see. Reading down is the order the snaps were played — not the clock, so a two-minute drill gets the same room as any other fourteen snaps. This game is final.
Bills←49ers→
Q1Q2Q3Q4
J.Allen FUMBLES−14% win probabilitymoment 3 of 4
(1:34) 17-J.Allen FUMBLES (Aborted) at BUF 0, RECOVERED by SF-54-F.Warner at BUF 3.
Q1 1:34 · Bills · 1st & 10 at BUF 1 · gained nothing · -5.49 EP · −13.9% win probability
162 snaps placed · 11 without a recorded yard line, left off the map · 4 marked moments — the largest win-probability swings, one per drive.
The Film Room · post-game
Post-game film: 173 plays across 19 drives, personnel groupings on 173 snaps. Everything here paints once the weekly sync ingests the game — there is no live play-level feed in this product, so nothing on this page updates while a game is being played.
Possession by possession
The field rail
10 of 19 drives ended in points. The longest march was SF moving 97 yards from the SF 2 for a turnover on downs. Each bar is the ground a drive actually covered; SF attacks right, BUF attacks left. Hatching marks a trip inside the twenty.
Every snap
Play stream
173 of 173 plays
Team
Quarter
Down
Play type
Expected points added
Event
Charted
Plays shown
173
EPA per play
+0.12
Success rate
51%
Yards
851
Who was on the field
Personnel groupings
Offensive grouping on every pass and run. A group needs five snaps in this game before it gets a number — under that the sample is a coin flip and the cell reads a dash instead. The names of the eleven on the field are only recorded from 2023 onward, so this game gives the grouping without the roster.
Bills1 RB, 1 TE, 3 WR55+0.3965%
49ers1 RB, 1 TE, 3 WR29+0.0286%
49ers1 RB, 2 TE, 2 WR17+0.0759%
49ers2 RB, 1 TE, 2 WR12+0.4033%
Bills1 RB, 2 TE, 2 WR5-0.6240%
Bills1 RB, 0 TE, 4 WR4——
Bills1 RB, 3 TE, 1 WR2——
Bills1 RB, 3 TE, 0 WR1——
49ers2 RB, 2 TE, 1 WR1——
49ers2 RB, 3 TE, 0 WR1——
snapsepapass rate
173 plays · ranked by the win probability each one moved
Every play
Ball
When
Play
Only
Who
173 plays
Bar length is win probability the play moved
1st quarter37 plays
FormationJumboOffense on the fieldSix linemen, one back and three tight endsDefense on the fieldFive linemen, three linebackers and three backsRoute runCrosserCoverageCover 0, no safety helpMan or zoneManIn the boxEleven defendersRushing the passerSixPressure (charted)The passer was kept cleanTime to throw3.6 seconds
Turnover on downs13 plays, from the Bills 25 to the 49ers 1
Turnover on downs14 plays, from the 49ers 2 to the Bills 1
Offense on the fieldOne back, two tight ends and two receiversDefense on the fieldFour linemen, two linebackers and five backsIn the boxEight defenders
Fumble lost1 play
Bills049ers6
Bills049ers7
Touchdown4 plays, from the Bills 3 to the Bills 2
The period ended4 plays, from the Bills 23 to the Bills 35
2nd quarter44 plays
Bills649ers7
Bills749ers7
Touchdown5 plays, from the 49ers 30 to the 49ers 5
Punt6 plays, from the 49ers 19 to the 49ers 37
Bills1349ers7
Bills1449ers7
Touchdown16 plays, from the Bills 31 to the 49ers 4
Punt7 plays, from the 49ers 25 to the Bills 46
Bills1749ers7
Field goal9 plays, from the Bills 10 to the 49ers 19
3rd quarter44 plays
Bills1749ers10
Field goal10 plays, from the 49ers 25 to the Bills 25
Bills2349ers10
Bills2449ers10
Touchdown14 plays, from the Bills 25 to the 49ers 23
Intercepted3 plays
Bills2749ers10
Field goal6 plays, from the 49ers 5 to the 49ers 2
Bills2749ers16
Bills2749ers17
Touchdown8 plays, from the 49ers 25 to the Bills 6
The period ended3 plays
4th quarter48 plays
Bills3349ers17
Bills3449ers17
Touchdown11 plays, from the Bills 40 to the 49ers 28
Intercepted10 plays, from the 49ers 25 to the Bills 1
Punt8 plays, from the Bills 2 to the Bills 23
Bills3449ers23
Bills3449ers24
Touchdown15 plays, from the 49ers 27 to the Bills 5
The period ended3 plays
Win probability is the league play-by-play model, 98.5% of plays · a dash means none was published
