Motion-blurred skater in a Philadelphia Flyers sweater
Breakdown · BOS at PHI

Flyers run the Bruins off the ice on the underlying numbers

The verdict · earned

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

BOS 1 · PHI 2
◆ By the ModelJul 12, 10:31 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

Philadelphia's 2-1 overtime victory over Boston looked far tighter than the numbers suggest. The Flyers controlled 65% of expected goals at 5v5 (3.49–1.91), out-executing the Bruins in possession, shot quality, and dangerous territory throughout.

The Flyers' dominance showed in every outlet. They held 62% of shot attempts, 31 to 19, and generated 5 high-danger chances against the Bruins' 2. Shot quality reveals why possession mattered: Philadelphia posted 0.062 expected goals per shot versus Boston's 0.040. That gap means the Flyers weren't just shooting more—they were positioning deeper, crashing harder, and creating 3 rebound opportunities, one of which led to a goal.

One goaltender held this game together: J. Korpisalo for Boston. He stopped 29 of 31 shots for a 0.935 save percentage, beating his expected performance by 1.49 goals and nearly stealing a result the underlying play didn't warrant. The Flyers' D. Vladar matched the excellence with 18 of 19 saves and a 0.947 SV%, though against far softer volume.

Even the variance tells the story. Philadelphia underperformed its xG by 1.49 goals; Boston underperformed by 0.91. Superior metrics finally converted when Porter Martone ended it with a wrist shot from the slot at 02:31 of overtime.

The breakdown in twelve frames

Swipe it

Every number is from this page
Final · OT · Apr 5
BOS
1
PHI
2

Flyers run the Bruins off the ice on the underlying numbers

Chances 1.9 – 3.5Did they deserve it? →
Did they deserve it?

The Flyers earned this one.

Expected goals · chance value
BOS
1.91
PHI
3.49
35% of the chances65%

The board read BOS 1, PHI 2. The chances read BOS 1.9, PHI 3.5.

Our xG model · NHL play-by-play · all situations
Luck check
PHI
−1.5
goals above expected
PHI3.49 expected · 2 scored
Expected
Scored
BOS1.91 expected · 1 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 04:19PHIC. Dvorak0–1
  2. P3 00:35BOSP. ZachaPP1–1
  3. OT 02:31PHIP. MartonePP1–2
NHL play-by-play · chance value from our xG model
Where the shots came from
BOS
32 shots
1
Final
74 shots
PHI
42 shots
2
BOS attackPHI attack
BOS PHI Goal
32
shots · 1 in
42
shots · 2 in
Every unblocked shot · press play to replay it
Chances by danger
BOSPHI
1 / 2
0.38 xG
High danger
1 / 5
1.41 xG
0 / 9
0.99 xG
Medium
1 / 14
1.47 xG
0 / 37
0.54 xG
Low
0 / 37
0.61 xG

High-danger looks: BOS 1 of 2, PHI 1 of 5.

Danger tiers by our xG model · high ≥ 20% chance
In the net
B+
J. Korpisalo
+1.5
BOS · 29/31
B+
D. Vladar
+0.9
PHI · 18/19
The numbers, checked
BACKCHECK

Flyers 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 3–6
  1. 04:19PHIC. Dvorak(P. Martone, R. Ristolainen)0–1
2ndshots 11–11no goals
    3rdshots 5–10
    1. 00:35BOSP. Zachapower play(C. Mittelstadt, D. Pastrnak)1–1
    OTshots 0–4
    1. 02:31PHIP. Martonepower play(C. Dvorak, T. Zegras)1–2

    score reads BOS–PHI

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

    The numbers

    XGBoost xG · NHL play-by-play
    3.49
    PHI chances
    Goals their shots were worth
    −1.5
    Finishing
    Goals below what those chances were worth
    1.015
    PHI puck luck
    About 1.000 — a normal night for bounces
    53.8%
    Shot attempts
    Over half — they had the puck more
    Split by club

    Who controlled the game

    1.91Expected goals3.49
    PHI 65% of the chance quality
    19Shots on goal31
    2High-danger chances5
    48All attempts (Corsi)56
    Adjusted for score: BOS 49% · PHI 51%
    Faceoffs · PHI won88%off44%neu50%def
    Source · NHL play-by-play · XGBoost xG
    How the game was won

    The danger ladder

    shotsgoalsexpected
    High dangerslot & crease
    BOS1 / 2 · 0.38 xG
    PHI1 / 5 · 1.41 xG
    Medium dangermid-range
    BOS0 / 9 · 0.99 xG
    PHI1 / 14 · 1.47 xG
    Low dangerperimeter & point
    BOS0 / 37 · 0.54 xG
    PHI0 / 37 · 0.61 xG

    BOS went 0-for-9 from medium danger on 0.99 expected goals — 1.0 left on the table.

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

    Finishing vs expected

    expectedactual
    BOS
    1 G · 1.91 xG · -0.9
    PHI
    2 G · 3.49 xG · -1.5
    01234

    BOS finished -0.9 against expected, PHI -1.5.

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

    Shot diet

    goalsshots
    BOS
    SNAP0/5
    WRIST1/12
    TIP IN0/7
    SLAP0/5
    BACKHAND0/1
    WRAP AROUND0/1
    DEFLECTED0/1
    OTHER0/16
    PHI
    SNAP1/21
    WRIST1/11
    TIP IN0/3
    SLAP0/4
    BACKHAND0/2
    WRAP AROUND0/1
    DEFLECTED0/0
    OTHER0/14
    BOS
    PHI
    Off the rush
    0 G on 22
    1.30 xG
    1 G on 26
    2.62 xG
    Off rebounds
    0 G on 1
    0.13 xG
    1 G on 3
    0.54 xG

    Snap shots carried the volume: BOS went 0-for-5, PHI 1-for-21.

    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 · 29/31 · .935
    +1.5
    saved above expected
    B+
    the night
    By dangerG/attxGsaved
    High danger1/51.4+0.4
    Medium1/141.5+0.5
    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

    D. Vladar
    PHI · 18/19 · .947
    +0.9
    saved above expected
    B+
    the night
    By dangerG/attxGsaved
    High danger1/20.4-0.6
    Medium0/91.0+1.0
    Low0/370.5+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

    74 shots · press play to watch the game back

    Where the shots came from

    NHL play-by-play coordinates
    BOS
    32 shots
    1
    Final
    74 shots
    PHI
    42 shots
    2
    BOS attackPHI attack
    BOS PHI Goal

    Each club shoots toward its own end — BOS left, PHI 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
    C. Dvorak
    #22 · C · PHI
    1 G · 1 A · 1 SOG · 20:04 on ice · +1
    P. Martone
    #94 · R · PHI
    1 G · 1 A · 5 SOG · 17:12 on ice · +1
    R. Ristolainen
    #55 · D · PHI
    0 G · 1 A · 2 SOG · 22:47 on ice · +1
    Ranked from the box score — points first · Backcheck
    What the model said beforehand

    Before the game

    Written Sun, Apr 5
    Open the pre-game read
    Written from the numbers

    The read

    Edited for clarity
    ◆ By the ModelJul 12, 10:30 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

    The model projects a 2.3–2.6 PHI game with Philadelphia at 55% win probability—as close to a pick'em as exists.

    Philadelphia's advantage runs deeper than the scoreline. The Flyers own the underlying play at 51.0% 5v5 xG against Boston's 47.0%, a meaningful gap reflecting genuine control. But Boston is running hot. The Bruins' 1.023 PDO signals regression is coming; expect the model's tightness to persist until shot quality catches up.

    J. Swayman enters on a back-to-back. Watch for a backup start or a fatigued starter—that decision alone could shift the edge.

    Viktor Arvidsson is Boston's offensive engine, generating 1.04 xG per 60 while riding an unsustainable 13.0% shooting rate to 18 goals and 24 assists. He'll draw Philadelphia's top assignment. Tanner Jeannot operates at a lower volume (0.75 xG/60, 6 goals, 14 assists) with 2 high-danger chances; his 8.3% shooting rate suggests he's overperforming the underlying play.

    Philadelphia counters with Owen Tippett (0.88 xG/60, 19 goals, 18 assists, 2 HD goals) and Christian Dvorak (0.81 xG/60, 12 goals, 21 assists, 3 HD goals, 11.2% shooting). Tippett's underlying numbers edge Arvidsson's, while Dvorak sits closer to sustainable conversion rates. Both should find space against Boston's weak link, Elias Lindholm.

    The Flyers' own defensive vulnerability—Dvorak on the perimeter—may matter less given Boston's tepid offensive efficiency. Both clubs generate chances without the explosive output either would need for a decisive edge.

    This lands exactly where the model says: a coin flip between a team with better luck and a team with better play.

    What the model said beforehand

    The model's lean

    PHI 55%
    55%
    PHI
    Model favorite
    45%
    55%
    BOS50PHI

    PHI by 10 points of win probability — a modest lean. Projected score BOS 2.3–2.6 PHI; 19% 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 →PHI
    47.0%51.0%
    49.0%48.0%
    2.392.26
    2.672.20
    2.221.96
    1.821.82
    1.0231.008

    The season numbers split 3–3 — no clear process edge — and the luck row (1.023 vs 1.008) says BOS has been getting the bounces, which tends not to last.

    Source · NHL stats API + our xG · 5v5
    Form · Last 10
    BOS
    6-3-1
    +9 GD · 1d rest
    PHI
    7-3-0
    +10 GD · 2d rest
    1.023
    BOS PDO
    Luck gauge · drifts to 1.000
    1.008
    PHI PDO
    Luck gauge · drifts to 1.000
    What decides it

    Keys to the game

    Where the edges live
    • The Flyers 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 Flyers own the underlying play — 51.0% 5v5 xG vs 47.0%.
    • 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.909 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.

    PHI
    Expected in goal
    D. Vladar
    2 days rest.955 last start
    Backup Dan Vladar · +13.8 GSAx this season

    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
    PHI
    Owen Tippett19G 18A
    0.88 xG/60 · 2 HD · 12.1% sh
    Christian Dvorak12G 21A
    0.81 xG/60 · 3 HD · 11.2% sh
    Keep going

    Where to next