Motion-blurred skater in a Pittsburgh Penguins sweater
Breakdown · BOS at PIT

Penguins run the Bruins off the ice on the underlying numbers

The verdict · earned

The Penguins earned it — the game and the expected-goals battle both.

BOS 4 · PIT 5
◆ By the ModelJul 12, 6:12 AMxG: xgboost-0.758Edited for clarityDrafted from NHL play-by-play by Backcheck's model, worded for clarity by an AI editor that may not change a number. Nobody at Backcheck was at the rink. How this works

Pittsburgh's 5-4 overtime win understates their dominance: they controlled 64% of 5v5 expected goals, turning a massive advantage in shot quality into a narrow victory.

The Penguins generated 40 shot attempts to Boston's 28, but the bigger story was how they shot. Pittsburgh's shots carried 0.073 xG per shot, well above Boston's 0.055—meaning they hunted better looks from better ice. High-danger chances reinforced the gap: 8–3. That quality edge translated to 5.49 expected goals versus 3.09.

Goaltending complicated the narrative. A. Silovs faced 28 shots and finished -0.91 against expected, meaning the Bruins' scoreline inflated his performance: at 0.857 SV%, he underperformed what the expected-goals model would predict for that volume. Meanwhile, J. Korpisalo faced tougher looks and still put up 0.875 SV%—Boston's overperformance (0.91 goals over xG) masked middle-of-the-road puck-stopping.

Both teams were surgical in transition. Pittsburgh scored 4 goals on 40 rush chances; Boston matched that same conversion rate on just 26 rushing chances. Pittsburgh also crashed the net effectively, generating 6 rebound opportunities and converting 1—the kind of offensive recycling that keeps pressure mounting.

The turning point arrived early in overtime: Tommy Novak's snap shot from the high slot at 00:17, a finish that epitomized Pittsburgh's edge in chance quality all night.

The breakdown in twelve frames

Swipe it

Every number is from this page
Final · OT · Mar 8
BOS
4
PIT
5

Penguins run the Bruins off the ice on the underlying numbers

Chances 3.1 – 5.5Did they deserve it? →
Did they deserve it?

The Penguins earned this one.

Expected goals · chance value
BOS
3.09
PIT
5.49
36% of the chances64%

The board read BOS 4, PIT 5. The chances read BOS 3.1, PIT 5.5.

Our xG model · NHL play-by-play · all situations
Luck check
PIT
−0.5
goals above expected
PIT5.49 expected · 5 scored
Expected
Scored
BOS3.09 expected · 4 scored
Expected
Scored

Both sides finished close to what their chances were worth. This one was earned on the ice.

PDO = sh% + sv% · drifts to 1.000 over a season
Every goal, in order
  1. P1 09:27BOSP. ZachaPP1–0
  2. P2 08:47BOSP. Zacha2–0
  3. P2 12:23BOSD. Pastrnak3–0
  4. P2 14:44PITE. ChinakhovPP3–1
  5. P3 06:02PITC. Dewar3–2
  6. P3 06:35PITA. Mantha3–3
  7. P3 08:34BOSP. Zacha4–3
+2 more on the full breakdown
NHL play-by-play · chance value from our xG model
Where the shots came from
BOS
41 shots
4
Final
98 shots
PIT
57 shots
5
BOS attackPIT attack
BOS PIT Goal
41
shots · 4 in
57
shots · 5 in
Every unblocked shot · press play to replay it
Chances by danger
BOSPIT
2 / 3
0.63 xG
High danger
1 / 8
1.90 xG
2 / 16
1.88 xG
Medium
3 / 23
2.91 xG
0 / 37
0.57 xG
Low
1 / 44
0.69 xG

High-danger looks: BOS 2 of 3, PIT 1 of 8.

Danger tiers by our xG model · high ≥ 20% chance
In the net
B
J. Korpisalo
+0.5
BOS · 35/40
D-
A. Silovs
−0.9
PIT · 24/28
The numbers, checked
BACKCHECK

Penguins run the Bruins off the ice on the underlying numbers

A model, not a newsroom. Every number on these frames comes from the NHL's play-by-play and our own models. Nothing was watched, guessed or heard from anyone.

Read the full breakdown
backcheckreport.com
01 / 08 · Final
Every goal, in order

How it happened

NHL play-by-play
1stshots 9–9
  1. 09:27BOSP. Zachapower play(M. Geekie, C. McAvoy)1–0
2ndshots 8–16
  1. 08:47BOSP. Zacha(V. Arvidsson, J. Aspirot)2–0
  2. 12:23BOSD. Pastrnak3–0
  3. 14:44PITE. Chinakhovpower play(R. Rakell, E. Karlsson)3–1
3rdshots 11–14
  1. 06:02PITC. Dewar(R. Shea)3–2
  2. 06:35PITA. Mantha(T. Novak, I. Solovyov)3–3
  3. 08:34BOSP. Zacha(V. Arvidsson, J. Aspirot)4–3
  4. 11:18PITA. Mantha(P. Wotherspoon, E. Karlsson)4–4
OTshots 0–1
  1. 00:17PITT. Novak4–5

score reads BOS–PIT

Source · NHL play-by-play (api-web.nhle.com)
Process vs result

The numbers

XGBoost xG · NHL play-by-play
5.49
PIT chances
Goals their shots were worth
−0.5
Finishing
Goals below what those chances were worth
0.995
PIT puck luck
About 1.000 — a normal night for bounces
57.3%
Shot attempts
Over half — they had the puck more
Split by club

Who controlled the game

3.09Expected goals5.49
PIT 64% of the chance quality
28Shots on goal40
3High-danger chances8
56All attempts (Corsi)75
Adjusted for score: BOS 39% · PIT 61%
Faceoffs · PIT won44%off52%neu53%def
Source · NHL play-by-play · XGBoost xG
How the game was won

The danger ladder

shotsgoalsexpected
High dangerslot & crease
BOS2 / 3 · 0.63 xG
PIT1 / 8 · 1.90 xG
Medium dangermid-range
BOS2 / 16 · 1.88 xG
PIT3 / 23 · 2.91 xG
Low dangerperimeter & point
BOS0 / 37 · 0.57 xG
PIT1 / 44 · 0.69 xG

BOS went 2-for-3 from high danger on 0.63 expected goals — 1.4 above expected.

Source · Backcheck xG model · NHL play-by-play
The luck layer

Finishing vs expected

expectedactual
BOS
4 G · 3.09 xG · +0.9
PIT
5 G · 5.49 xG · -0.5
0123456

BOS finished +0.9 against expected, PIT -0.5.

Source · Backcheck xG model
Shot types · rush and rebound chancesopen +
What they shot — and what went in

Shot diet

goalsshots
BOS
WRIST1/29
TIP IN0/5
SLAP0/3
BACKHAND2/2
SNAP1/1
DEFLECTED0/1
OTHER0/15
PIT
WRIST1/37
TIP IN0/6
SLAP0/4
BACKHAND3/5
SNAP1/5
DEFLECTED0/0
OTHER0/18
BOS
PIT
Off the rush
4 G on 26
2.34 xG
4 G on 40
3.82 xG
Off rebounds
0 G on 0
0.00 xG
1 G on 6
1.06 xG

Wrist shots carried the volume: BOS went 1-for-29, PIT 1-for-37. BOS scored 4 of theirs off the rush.

Source · Backcheck xG model · NHL shot types
New to these numbers?

Two things happened in this game: who created the better chances, and who put the puck in the net. They are not the same thing, and this page separates them on purpose.

The one to watch is expected goals— the best single read on who deserved to win. When it disagrees with the scoreboard, that disagreement is usually the story. Nothing here is a projection; every figure is computed from this game's play-by-play. Full glossary →

xG
Expected goals. Every shot scored by how often that exact look goes in. 2.5 xG means the chances were worth about two and a half goals.
HD
High-danger chances — shots from the slot and the crease, where shots actually become goals.
Corsi
Every shot attempt, including the ones that missed or got blocked. A rough read on who had the puck.
Adj.
Score-adjusted. Teams that trail shoot more and teams that lead sit back, so this corrects the attempt count for the scoreboard.
GSAx
Goals saved above expected. A positive number means the goalie stopped more than an average goalie would have on those shots.
PDO
Shooting % plus save % — a luck gauge. It sits near 1.000 over a season, so a game far from it usually means the bounces decided it.
Shot by shot

In the net

Graded on goals saved above expected
J. Korpisalo
BOS · 35/40 · .875
+0.5
saved above expected
B
the night
By dangerG/attxGsaved
High danger1/81.9+0.9
Medium3/232.9-0.1
Low1/440.7-0.3

A+ ≥ +2.5 saved above expected · A ≥ +1.5 · B+ ≥ +0.75 · B ≥ +0.25 · C ≥ −0.25 · D ≥ −0.75 · F below −1.5

A. Silovs
PIT · 24/28 · .857
-0.9
saved above expected
D-
the night
By dangerG/attxGsaved
High danger2/30.6-1.4
Medium2/161.9-0.1
Low0/370.6+0.6

A+ ≥ +2.5 saved above expected · A ≥ +1.5 · B+ ≥ +0.75 · B ≥ +0.25 · C ≥ −0.25 · D ≥ −0.75 · F below −1.5

98 shots · press play to watch the game back

Where the shots came from

NHL play-by-play coordinates
BOS
41 shots
4
Final
98 shots
PIT
57 shots
5
BOS attackPIT attack
BOS PIT Goal

Each club shoots toward its own end — BOS left, PIT right — the way you would watch it. A dot's size is how dangerous the look was, from distance and angle; it is a proxy for shot quality, not the xG model the article is written from. Hover a dot for the shooter and the clock.

Ranked from the box score

Three stars

Points first
Three stars · computed, not voted
P. Zacha
#18 · C · BOS
3 G · 0 A · 4 SOG · 16:59 on ice
E. Karlsson
#65 · D · PIT
0 G · 2 A · 6 SOG · 24:20 on ice · +1
T. Novak
#18 · C · PIT
1 G · 1 A · 1 SOG · 15:23 on ice · +4
Ranked from the box score — points first · Backcheck
What the model said beforehand

Before the game

Written Sun, Mar 8
Open the pre-game read
Written from the numbers

The read

Edited for clarity
◆ By the ModelJul 12, 6:11 AMEdited for clarityDrafted from NHL play-by-play by Backcheck's model, worded for clarity by an AI editor that may not change a number. Nobody at Backcheck was at the rink. How this works

Pittsburgh enters at 55% win probability in a projected 2.5–2.8 game. The Penguins control the underlying play: 51.0% xG at five-on-five versus Boston's 47.0%, and they've held a slight Corsi% edge (50.0% to 49.0%) across the season.

Boston's issue starts with PDO. At 1.023, the Bruins are running hot compared to Pittsburgh's 1.012—regression is mathematical. Their 13.0% shooting rate compounds this risk; it rests on elite execution from Viktor Arvidsson (18G 24A, 1.04 xG/60, 2 HD goals), a secondary option in Tanner Jeannot (6G at 8.3% shooting, 0.75 xG/60), and team-wide 0% hard-chance and 0% rebound-goal rates that won't hold.

Pittsburgh's production is grounded by comparison. Rickard Rakell (13G 13A, 1.01 xG/60, 12.1% shooting) runs closer to underlying talent; his 3 HD goals reflect more realistic efficiency. Filip Hallander (1.28 xG/60) was flagged as a watch name before undergoing further evaluation following his recall from his conditioning loan.

Both S. Skinner and J. Swayman face back-to-back pressure; expect backup appearances or conservative starts. Boston's defensive liability is Elias Lindholm; Pittsburgh's is Caleb Jones.

The xG% gap and Boston's inevitable PDO regression drive the edge. Lean Pittsburgh at 55%.

What the model said beforehand

The model's lean

PIT 55%
55%
PIT
Model favorite
45%
55%
BOS50PIT

PIT by 10 points of win probability — a modest lean. Projected score BOS 2.5–2.8 PIT; 18% chance it's tied after 60.

Source · Backcheck Poisson projection · season scoring rates
Season rates · 5v5

Tale of the tape

NHL stats API · our xG
BOS← edge
edge →PIT
47.0%51.0%
49.0%50.0%
2.392.66
2.672.55
2.222.45
1.822.12
1.0231.012

PIT holds 5 of 6 process categories — and the luck row (1.023 vs 1.012) says BOS has been getting the bounces, which tends not to last.

Source · NHL stats API + our xG · 5v5
Form · Last 10
BOS
5-2-3
+1 GD · 1d rest
PIT
4-3-3
+3 GD · 1d rest
1.023
BOS PDO
Luck gauge · drifts to 1.000
1.012
PIT PDO
Luck gauge · drifts to 1.000
What decides it

Keys to the game

Where the edges live
  • The Penguins own the underlying play — 51.0% 5v5 xG vs 47.0%.
Regression watch
  • The Bruins' PDO is 1.023 — running hot, expect some regression.
Things to watch
  • The Penguins own the underlying play — 51.0% 5v5 xG vs 47.0%.
  • S. Skinner is on a back-to-back — watch for a backup start or a tired starter.
  • J. Swayman is on a back-to-back — watch for a backup start or a tired starter.
  • The Bruins' PDO is 1.023 — running hot, expect some regression.
Last game's lineup · confirmed at warm-up

Lineups

NHL box score
BOS
Expected in goal
J. Swayman
back-to-back.957 last start
Backup Jeremy Swayman · +28.8 GSAx this season
Back-to-back: the backup often gets this one. Treat the starter as unconfirmed.

No completed game on file for this club yet.

PIT
Expected in goal
S. Skinner
back-to-back.813 last start
Backup Stuart Skinner · +8.3 GSAx this season
Back-to-back: the backup often gets this one. Treat the starter as unconfirmed.

No completed game on file for this club yet.

Lineups are the players who dressed in each club's last game, with their minutes; clubs confirm tonight's at warm-up. Every player this preview names was in that lineup.

Computed danger · scouting

Players to watch

NHL stats API · our xG
BOS
Viktor Arvidsson18G 24A
1.04 xG/60 · 2 HD · 13.0% sh
Tanner Jeannot6G 14A
0.75 xG/60 · 2 HD · 8.3% sh
PIT
Filip Hallander0G 3A
1.28 xG/60 · 0 HD · 0.0% sh
Rickard Rakell13G 13A
1.01 xG/60 · 3 HD · 12.1% sh
Keep going

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