Motion-blurred skater in a gold and black sweater
Breakdown · UTA at BOS

Bruins pull away from the Mammoth

The verdict · stolen

The Bruins stole one. They lost the expected-goals battle 2.83–2.55 and won anyway.

UTA 1 · BOS 4
◆ By the ModelJul 11, 8:31 PMxG: 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

Boston's 4-1 victory conceals a close underlying game: expected goals favored Utah 2.83–2.55, yet the Bruins scored four. Goaltending variance decided it. J. Swayman saved 1.8 goals above expected. V. Vanecek surrendered 1.4 more than expected. Utah also squandered quality chances.

Boston held 52% of shot attempts (23–21 on goal), though Utah generated the more dangerous looks: 53% of expected goals versus Boston's 47%. High-danger chances favored Boston 4–3, and the Bruins converted ruthlessly — 3 of 4 from the danger zone (75%). Utah created 5 rebound opportunities and scored none. Boston created 3 and converted 2.

The Bruins were lethal on the rush: 2 goals on 20 rush chances. Michael Eyssimont's backhander from the doorstep (P3, 16:02) captured the clinical execution.

This wasn't a blowout rooted in dominance. It was a lesson in goaltending depth and execution gaps: Utah wasted quality, Boston cashed in.

The breakdown in twelve frames

Swipe it

Every number is from this page
Final · Dec 16
UTA
1
BOS
4

Bruins pull away from the Mammoth

Chances 2.8 – 2.5Did they deserve it? →
Did they deserve it?

Dead even on chances. The Bruins took it anyway.

Expected goals · chance value
UTA
2.83
BOS
2.55
53% of the chances47%

The board read UTA 1, BOS 4. The chances read UTA 2.8, BOS 2.5.

Our xG model · NHL play-by-play · all situations
Luck check
BOS
+1.4
goals above expected
BOS2.55 expected · 4 scored
Expected
Scored
UTA2.83 expected · 1 scored
Expected
Scored

The Mammoth left 1.8 goals on the table against what their chances were worth.

PDO = sh% + sv% · drifts to 1.000 over a season
Every goal, in order
  1. P1 08:34UTAB. HaytonPP1–0
  2. P1 16:01BOSM. GeekiePP1–1
  3. P2 00:23BOSM. Geekie1–2
  4. P3 10:16BOSC. Mittelstadt1–3
  5. P3 16:02BOSM. Eyssimont1–4
NHL play-by-play · chance value from our xG model
Where the shots came from
UTA
35 shots
1
Final
70 shots
BOS
35 shots
4
UTA attackBOS attack
UTA BOS Goal
35
shots · 1 in
35
shots · 4 in
Every unblocked shot · press play to replay it
Chances by danger
UTABOS
0 / 3
0.66 xG
High danger
3 / 4
0.88 xG
1 / 16
1.78 xG
Medium
0 / 11
1.17 xG
0 / 40
0.40 xG
Low
1 / 33
0.50 xG

The Mammoth went 0 for 3 from the slot.

Danger tiers by our xG model · high ≥ 20% chance
In the net
A
J. Swayman
+1.8
BOS · 20/21
D-
V. Vanecek
−1.4
UTA · 19/23
The numbers, checked
BACKCHECK

Bruins pull away from the Mammoth

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 13–7
  1. 08:34UTAB. Haytonpower play(S. Durzi, D. But)1–0
  2. 16:01BOSM. Geekiepower play(D. Pastrnak, E. Lindholm)1–1
2ndshots 3–8
  1. 00:23BOSM. Geekie(D. Pastrnak, N. Zadorov)1–2
3rdshots 5–8
  1. 10:16BOSC. Mittelstadt(P. Zacha, M. Khusnutdinov)1–3
  2. 16:02BOSM. Eyssimont1–4

score reads UTA–BOS

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

The numbers

XGBoost xG · NHL play-by-play
2.55
BOS chances
Goals their shots were worth
+1.4
Finishing
Goals above what those chances were worth
1.066
BOS puck luck
Above 1.000 — the bounces went their way
44.9%
Shot attempts
Under half — they were outshot
Split by club

Who controlled the game

2.83Expected goals2.55
UTA 53% of the chance quality
21Shots on goal23
3High-danger chances4
59All attempts (Corsi)48
Adjusted for score: UTA 58% · BOS 42%
Faceoffs · BOS won48%off41%neu64%def
Source · NHL play-by-play · XGBoost xG
How the game was won

The danger ladder

shotsgoalsexpected
High dangerslot & crease
UTA0 / 3 · 0.66 xG
BOS3 / 4 · 0.88 xG
Medium dangermid-range
UTA1 / 16 · 1.78 xG
BOS0 / 11 · 1.17 xG
Low dangerperimeter & point
UTA0 / 40 · 0.40 xG
BOS1 / 33 · 0.50 xG

BOS went 3-for-4 from high danger on 0.88 expected goals — 2.1 above expected.

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

Finishing vs expected

expectedactual
UTA
1 G · 2.83 xG · -1.8
BOS
4 G · 2.55 xG · +1.4
012345

UTA finished -1.8 against expected, BOS +1.4.

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

Shot diet

goalsshots
UTA
WRIST0/15
TIP IN1/6
SLAP0/7
BACKHAND0/3
SNAP0/1
DEFLECTED0/2
BETWEEN LEGS0/1
OTHER0/24
BOS
WRIST3/24
TIP IN0/6
SLAP0/2
BACKHAND1/1
SNAP0/2
DEFLECTED0/0
BETWEEN LEGS0/0
OTHER0/13
UTA
BOS
Off the rush
1 G on 24
1.96 xG
2 G on 20
1.67 xG
Off rebounds
0 G on 5
0.60 xG
2 G on 3
0.48 xG

Wrist shots carried the volume: UTA went 0-for-15, BOS 3-for-24. BOS scored 2 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
V. Vanecek
UTA · 19/23 · .826
-1.4
saved above expected
D-
the night
By dangerG/attxGsaved
High danger3/40.9-2.1
Medium0/111.2+1.2
Low1/330.5-0.5

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

J. Swayman
BOS · 20/21 · .952
+1.8
saved above expected
A
the night
By dangerG/attxGsaved
High danger0/30.7+0.7
Medium1/161.8+0.8
Low0/400.4+0.4

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

70 shots · press play to watch the game back

Where the shots came from

NHL play-by-play coordinates
UTA
35 shots
1
Final
70 shots
BOS
35 shots
4
UTA attackBOS attack
UTA BOS Goal

Each club shoots toward its own end — UTA left, BOS 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
D. Pastrnak
#88 · R · BOS
0 G · 2 A · 5 SOG · 19:40 on ice · +1
M. Geekie
#39 · C · BOS
2 G · 0 A · 3 SOG · 18:32 on ice · +1
S. Durzi
#50 · D · UTA
0 G · 1 A · 1 SOG · 23:02 on ice · -1
Ranked from the box score — points first · Backcheck
What the model said beforehand

Before the game

Written Tue, Dec 16
Open the pre-game read
Written from the numbers

The read

Edited for clarity
◆ By the ModelJul 11, 8:30 PMEdited 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

The model projects a UTA 2.6 - 2.5 BOS game with the Mammoth at 52% win probability. This is as close to a pick'em as you'll find.

Utah owns the underlying play. They're generating 52.0% of expected goals at 5v5 against Boston's 47.0%—a genuine territorial advantage. The Corsi numbers reinforce it: UTA controls 53.0% of shot attempts versus BOS's 49.0%, meaning they're dictating pace and space throughout the game.

Boston is running hot, which is where Utah's edge lives. The Bruins' PDO sits at 1.023 while Utah's is 1.003—Boston is converting at a rate that historically regresses. If the puck stops bouncing their way, the underlying dominance tips toward the Mammoth.

Dylan Guenther is Utah's engine. He's producing at 1.02 xG/60 with 28 goals and 15 assists, banking three high-danger goals on a 16.8% shooting rate—elite efficiency on elite volume. Daniil But operates at 1.01 xG/60 with 2 goals and 2 assists, posting a 5.6% shooting rate that suggests either volatility or regression waiting to happen.

Boston counters with Viktor Arvidsson, who's operating at 1.04 xG/60, the highest of these four players. His 18 goals and 24 assists show he's burying chances more consistently than Guenther despite lower volume generation. Tanner Jeannot is the outlier at 0.75 xG/60 with 6 goals, meaning his finishing has carried his point total—exactly the type of player who can crater if the puck stops bouncing his way.

Tactically, Utah will dictate play, but Boston has the dangerous finisher in Arvidsson. Utah needs to neutralize Guenther through defensive attention, though his three high-danger goals already show that won't be simple. Boston needs Jeannot to continue overperforming while suppressing Utah's territorial grip—a tall order given the shot-attempt margins.

Both teams show 0% high-danger goal rates and 0% rebound goal rates, which registers as incomplete data on situational finishing. Utah's defensive exposure is Maveric Lamoureux; Boston's is Elias Lindholm. Exploit those weaknesses and the game opens up.

This really is a coin flip. Utah's superior play-driving gives them the edge in a vacuum, but Boston's hot PDO and Arvidsson's finishing ability make them dangerous enough to steal it.

What the model said beforehand

The model's lean

UTA 52%
52%
UTA
Model favorite
52%
48%
UTA50BOS

UTA by 4 points of win probability — effectively a coin flip. Projected score UTA 2.6–2.5 BOS; 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
UTA← edge
edge →BOS
52.0%47.0%
53.0%49.0%
2.642.39
2.392.67
2.262.22
1.991.82
1.0031.023

UTA holds 5 of 6 process categories — and the luck row (1.003 vs 1.023) says BOS has been getting the bounces, which tends not to last.

Source · NHL stats API + our xG · 5v5
Form · No games yet
UTA
0-0-0
+0 GD · 0d rest
BOS
0-0-0
+0 GD · 0d rest
1.003
UTA PDO
Luck gauge · drifts to 1.000
1.023
BOS PDO
Luck gauge · drifts to 1.000
What decides it

Keys to the game

Where the edges live
  • The Mammoth own the underlying play — 52.0% 5v5 xG vs 47.0%.
  • The Mammoth drive Corsi at 53.0% — expect territorial tilt.
Regression watch
  • The Bruins' PDO is 1.023 — running hot, expect some regression.
Things to watch
  • The Mammoth own the underlying play — 52.0% 5v5 xG vs 47.0%.
  • The Mammoth drive Corsi at 53.0% — expect territorial tilt.
  • The Bruins' PDO is 1.023 — running hot, expect some regression.
Computed danger · scouting

Players to watch

NHL stats API · our xG
UTA
Dylan Guenther28G 15A
1.02 xG/60 · 3 HD · 16.8% sh
Daniil But2G 2A
1.01 xG/60 · 1 HD · 5.6% sh
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
Keep going

Where to next