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2021 Week 16 · Sun, Dec 26, 2021 · GEHA Field at Arrowhead Stadium
Final
SteelersPittsburgh10
BY 26final margin
ChiefsKansas City36
Pittsburgh Steelers 10 at Kansas City Chiefs 36. Final.
Chiefs -10.5 ✓O 44 ✓
The verdict · 2021 Week 16
Kansas City Chiefs 36, Steelers 10 — and it was over early.
It turned at Q1 14:25, 2nd and 12, on Diontae Johnson — 6.4 win-probability points to the Steelers on one snap, the largest move of the game, and it still was not enough.
The snaps that bent it
The biggest swing of the game · Q1 14:25 · 2nd and 12
Diontae Johnson
Steelers
(14:25) (No Huddle, Shotgun) 7-B.Roethlisberger pass short right to 18-D.Johnson pushed ob at PIT 41 for 18 yards (21-M.Hughes).
Chiefs closed -10.5 and covered, winning by 26.
Kansas City Chiefs 36–10 — never really in doubt late. Biggest swing: Q1 14:25, Steelers +6.4% win probability on one snap.
6.4
win-probability points on one snap
The largest move of the game. The two below are drawn against it.
Clyde Edwards-HelaireSteelersQ1 12:17(12:17) (Shotgun) 25-C.Edwards-Helaire right end to KC 27 for no gain (92-I.Loudermilk; 93-J.Schobert).
3.5pts
Tyreek HillChiefsQ1 11:00(11:00) (Shotgun) 15-P.Mahomes pass short left to 10-T.Hill to KC 40 for 10 yards (23-J.Haden).
4.2pts
What separated them
Throwing the ball
Chiefs won this one — +0.50 expected points per dropback, against Steelers at -0.37 expected points per dropback.
Chiefsthe gap went the way the scoreboard did
Giveaways
Chiefs won this one — no giveaways, against Steelers at 3 giveaways.
Chiefsthe gap went the way the scoreboard did
Every snap
Chiefs won this one — +0.23 expected points per snap, against Steelers at -0.28 expected points per snap.
Chiefsthe gap went the way the scoreboard did
Red zone
Chiefs won this one — 4 touchdowns on 7 trips, against Steelers at 1 touchdown on 4 trips.
2 other measures were inside a third of the league's own spread — two clubs doing the same thing, so they are not shown.
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 5.0 win-probability points apart on the average play, and 28 apart at the widest — with the model the more convinced about Steelers.
MarketModelmodel higher on Chiefshigher on Steelers172 of 183 plays carry both curves
(14:25) (No Huddle, Shotgun) 7-B.Roethlisberger pass short right to 18-D.Johnson pushed ob at PIT 41 for 18 yards (21-M.Hughes).
Swing −6.4 for ChiefsExpected points −2.23 for ChiefsThe model had Steelers 28 points higher than the market did.play 4
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 · 14:25KC +6% win prob(14:25) (No Huddle, Shotgun) 7-B.Roethlisberger pass short right to 18-D.Johnson pushed ob at PIT 41 for 18 yards (21-M.Hughes).
1st · 11:00KC +4% win prob(11:00) (Shotgun) 15-P.Mahomes pass short left to 10-T.Hill to KC 40 for 10 yards (23-J.Haden).
1st · 12:17PIT +3% win prob(12:17) (Shotgun) 25-C.Edwards-Helaire right end to KC 27 for no gain (92-I.Loudermilk; 93-J.Schobert).
1st · 15:00PIT +3% win prob(15:00) 22-N.Harris right end to PIT 23 for -2 yards (53-A.Hitchens, 22-J.Thornhill).
1st · 4:07PIT +3% win prob(4:07) 7-B.Roethlisberger pass deep right intended for 14-R.McCloud INTERCEPTED by 35-C.Ward at PIT 49. 35-C.Ward to PIT 49 for no gain (14-R.McCloud).
1st · 12:29KC +3% win prob(12:29) 10-C.Waitman punts 58 yards to KC 9, Center-46-C.Kuntz. 17-M.Hardman pushed ob at KC 27 for 18 yards (48-D.Tuszka).
SettledThe modelled figures are the league play-by-play model's, not ours.
How the points landed
The margin ledger
Clyde Edwards-Helaire's 1-yard rushing touchdown with 4:12 left in the 1st put Kansas City Chiefs ahead for good. The lead never changed over the 8 scores that followed.
Lead
1st4:12Clyde Edwards-Helaire·1-yd TD run1-yard rushing touchdownLead never changed again+70–7
1st1:14Byron Pringle·5-yd TD catch5-yard touchdown catchfrom Patrick Mahomesfrom Patrick Mahomes+70–14
2nd8:50Elliott Fry·44-yd field goal44-yard field goalholder J.Townsend · snap J.Winchester+30–17
2nd2:19Mecole Hardman·8-yd TD catch8-yard touchdown catchfrom Patrick Mahomesfrom Patrick Mahomes · kick no good, wide left+60–23
3rd9:00Byron Pringle·16-yd TD catch16-yard touchdown catchfrom Patrick Mahomesfrom Patrick Mahomes+70–30
3rd3:37Chris Boswell·34-yd field goal34-yard field goalholder C.Waitman · snap C.Kuntz+33–30
4th12:01Elliott Fry·34-yd field goal34-yard field goalholder J.Townsend · snap J.Winchester+33–33
4th9:46Elliott Fry·30-yd field goal30-yard field goalholder J.Townsend · snap J.Winchester+33–36
4th2:59Diontae Johnson·15-yd TD catch15-yard touchdown catchfrom Ben Roethlisbergerfrom Ben Roethlisberger+710–36
9 scores · bar length is the lead after each one
Down-to-down truth
Situational splits
Steelerscategory by categoryChiefs
Steelers1–6Chiefs
303Total yards381
4.4Yards per play5.7
42%Success rate49%
38%Third-down rate36%
1Red-zone touchdowns4
4Explosive plays4
20First downs25
2Sacks taken2
3Turnovers0
The read
Chiefs ahead 6–1 on categories, including the biggest gap of the duel — turnovers.
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, ±0.50 points.
Every snapexpected points added per play, all downs
−0.28Steelers: −0.28 expected points added per play
+0.23Chiefs: +0.23 expected points added per play
Dropping backexpected points added per dropback
−0.37Steelers: −0.37 expected points added per play
+0.50Chiefs: +0.50 expected points added per play
Running itexpected points added per rush
−0.11Steelers: −0.11 expected points added per play
−0.02Chiefs: −0.02 expected points added per play
Neither side “wins” volume or play-calling mix, so neither is drawn as a duel: Steelers ran 69 snaps at a 65% dropback rate against Chiefs’s 67 at 48%. Red-zone trips: Steelers 4, Chiefs 7.
NoteChiefs won the down-to-down efficiency fight: 0.23 expected points added per play vs -0.28.
Derived from the play-by-play, no model
The Read
8 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.
low through week 16Against their seasonOver Expected
KC's pass rate over expected, −4.5 pts, is past their previous low of +0.8 pts in week 14 — the lowest of their 15 charted games through week 16.
2.4 times their own weekly swing below their number.
A 3.0-swing turn from week 15.
67 snaps this game, floor 20 — 17 of their games behind the ruler, and their own week-to-week swing is 5.7 points.
PIT's sack or hit rate turned over: 21.6% in week 15 against 9.4% here — they got home then and stayed blocked now, a turn of 2.0 of their own weekly swings across the two.
32 dropbacks this game, floor 12 — 17 of their games behind the ruler, and their own week-to-week swing is 6.0 points.
The season-grain rooms, pointed at this one game
Was this normal for them?
8 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 -17 pts to 25 pts
leaned — stayed blocked · −6.0 vs their 15.4%, and they swing ±6.0 week to week (−1.00× that swing) · 32 dropbacks
Chiefs6.7%
leaned — stayed blocked · −6.0 vs their 12.7%, and they swing ±5.4 week to week (−1.11× that swing) · 45 dropbacks
Play-action rate
Charted from 2022. The columns exist for 2021 and are entirely empty, which is not a season of data.
Blitz rate sent
Charted from 2022. The columns exist for 2021 and are entirely empty, which is not a season of data.
NoteKC's pass rate over expected was the night's one real departure: -4.5 pts, 13.7 points below their season mean of 9.2 pts and 2.4 times their own 5.7-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.
Pittsburgh Steelers
48 dressed · 6 inactive
76Chukwuma OkoraforT · Every snap100%72 snaps
65Dan MooreT · Every snap100%72 snaps
77John LeglueT · Every snap100%72 snaps
18Diontae JohnsonWR · Full-time90%65 snaps
7Ben RoethlisbergerQB · Full-time86%62 snaps
11Chase ClaypoolWR · Full-time82%59 snaps
22Najee HarrisRB · Heavy rotation78%56 snaps
81Zach GentryTE · Heavy rotation68%49 snaps
14Ray-Ray McCloudWR · Heavy rotation63%45 snaps
53Kendrick GreenC · Heavy rotation63%45 snaps
51Trai TurnerG · Heavy rotation61%44 snaps
15Cody WhiteWR · Rotational39%28 snaps
71Joe HaegT · Rotational39%28 snaps
60J.C. HassenauerC · Rotational38%27 snaps
13James WashingtonWR · Rotational31%22 snaps
87Kevin RaderTE · Situational24%17 snaps
24Benny SnellRB · Situational22%16 snaps
2Mason RudolphQB · Situational14%10 snaps
44Derek WattFB · Situational4%3 snaps
Inactive · 6
Chris WormleyDEBuddy JohnsonILBPressley HarvinPCameron NizialekPDwayne HaskinsQBPat FreiermuthTE
Kansas City Chiefs
48 dressed · 4 inactive
77Andrew WylieG · Every snap100%69 snaps
65Trey SmithG · Every snap100%69 snaps
52Creed HumphreyC · Full-time96%66 snaps
62Joe ThuneyG · Full-time96%66 snaps
57Orlando BrownT · Full-time96%66 snaps
15Patrick MahomesQB · Full-time91%63 snaps
13Byron PringleWR · Full-time80%55 snaps
83Noah GrayTE · Heavy rotation73%50 snaps
11Demarcus RobinsonWR · Heavy rotation67%46 snaps
17Mecole HardmanWR · Rotational44%30 snaps
31Darrel WilliamsRB · Rotational42%29 snaps
10Tyreek HillWR · Rotational42%29 snaps
81Blake BellTE · Rotational36%25 snaps
25Clyde Edwards-HelaireRB · Rotational30%21 snaps
40Derrick GoreRB · Rotational28%19 snaps
45Michael BurtonFB · Situational19%13 snaps
85Marcus KempWR · Situational16%11 snaps
19Josh GordonWR · Situational12%8 snaps
73Nick AllegrettiG · Situational10%7 snaps
4Chad HenneQB · Situational9%6 snaps
66Austin BlytheC · Situational6%4 snaps
70Prince Tega WanoghoT · Situational4%3 snaps
48Nakia Griffin-StewartTE · Situational4%3 snaps
Inactive · 4
Nick BoltonILBShane BuecheleQBLucas NiangTTravis KelceTE
1 player played under 8 snaps, so their shares read as a dash rather than a number. 1 line has no expected-points read and sits off the plane.
Expected points are modelled in full PPR, so the “vs expected” column stays in that unit whichever format the pills are set to. Switching the pills changes the points column, not the plane.
The field map
Every snap, where it happened
The whole game as one hundred yards. The Chiefs attack right, the Steelers 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.
Steelers←Chiefs→
Q1Q2Q3Q4
B.Roethlisberger pass−8% win probabilitymoment 3 of 4
(4:07) 7-B.Roethlisberger pass deep right intended for 14-R.McCloud INTERCEPTED by 35-C.Ward at PIT 49. 35-C.Ward to PIT 49 for no gain (14-R.McCloud).
Q1 4:07 · Steelers · 1st & 10 at PIT 25 · gained nothing · -3.89 EP · −7.7% win probability
170 snaps placed · 13 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: 183 plays across 21 drives, personnel groupings on 183 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
9 of 21 drives ended in points. The longest march was PIT moving 85 yards from the PIT 15 for a touchdown. Each bar is the ground a drive actually covered; KC attacks right, PIT attacks left. Hatching marks a trip inside the twenty.
Every snap
Play stream
183 of 183 plays
Team
Quarter
Down
Play type
Expected points added
Event
Charted
Plays shown
183
EPA per play
-0.04
Success rate
43%
Yards
684
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.
Steelers1 RB, 1 TE, 3 WR60-0.3163%
Chiefs1 RB, 1 TE, 3 WR44+0.2968%
Chiefs2 RB, 1 TE, 2 WR11-0.159%
Chiefs1 RB, 2 TE, 2 WR9+0.0511%
Steelers1 RB, 0 TE, 4 WR5+0.06100%
Steelers2 RB, 1 TE, 2 WR2——
Chiefs2 RB, 1 TE, 1 WR1——
Chiefs2 RB, 1 TE, 0 WR1——
Steelers1 RB, 2 TE, 2 WR1——
Steelers2 RB, 0 TE, 3 WR1——
Chiefs1 RB, 1 TE, 2 WR1——
snapsepapass rate
183 plays · ranked by the win probability each one moved
Every play
Ball
When
Play
Only
Who
183 plays
Bar length is win probability the play moved
1st quarter38 plays
Punt7 plays, from the Steelers 25 to the Steelers 41
Steelers0Chiefs6
Steelers0Chiefs7
Touchdown16 plays, from the Chiefs 27 to the Steelers 1
Intercepted2 plays
Steelers0Chiefs13
Steelers0Chiefs14
Touchdown8 plays, from the Steelers 49 to the Steelers 5
The period ended4 plays, from the Steelers 20 to the Steelers 22
2nd quarter52 plays
Punt4 plays, from the Steelers 31 to the Steelers 37
Steelers0Chiefs17
Field goal10 plays, from the Chiefs 20 to the Steelers 26
No good10 plays, from the Steelers 25 to the Chiefs 18
Steelers0Chiefs23
Touchdown8 plays, from the Chiefs 26 to the Steelers 8
Turnover on downs6 plays, from the Steelers 25 to the Steelers 34
No good8 plays, from the Steelers 31 to the Steelers 20
The period ended6 plays, from the Steelers 29 to the Steelers 44
3rd quarter43 plays
Punt6 plays, from the Chiefs 25 to the Chiefs 34
Fumble lost2 plays, from the Steelers 30 to the Steelers 38
Steelers0Chiefs29
Steelers0Chiefs30
Touchdown8 plays, from the Chiefs 49 to the Steelers 16
Steelers3Chiefs30
Field goal19 plays, from the Steelers 30 to the Chiefs 11
The period ended8 plays, from the Chiefs 25 to the Steelers 46
4th quarter50 plays
Steelers3Chiefs33
Field goal6 plays, from the Steelers 39 to the Steelers 12
Fumble lost2 plays
Steelers3Chiefs36
Field goal4 plays
Steelers9Chiefs36
Steelers10Chiefs36
Touchdown19 plays, from the Steelers 15 to the Chiefs 15
Punt8 plays, from the Chiefs 25 to the Chiefs 31
The period ended11 plays, from the Steelers 39 to the Chiefs 19
Win probability is the league play-by-play model, 98.5% of plays · a dash means none was published
