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

J. Swayman stands tall as the Bruins edge the Red Wings

The verdict · coin flip

The Bruins won a genuine coin flip — neither side controlled the run of play.

BOS 4 · DET 2
◆ By the ModelJul 12, 8:22 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

Detroit dominated possession yet lost. The Red Wings held 62% of shot attempts (44–27 on goal) and nearly matched Boston's underlying production—expected goals split 4.91–4.85 in Detroit's favor—but Boston won 4–2. The difference: elite goaltending, clinical finishing, and Detroit's complete collapse on scoring chances.

J. Swayman delivered the deciding performance. He saved 42 of 44 shots (0.955 SV%), overperforming his expected mark by 2.91 goals—essentially stealing a game his team had no business winning on the metrics. More damaging: Swayman was perfect on high-danger chances, stopping all seven. J. Gibson made 23 saves on 26 shots (0.885 SV%, +1.85 expected), but couldn't overcome Detroit's wastefulness on prime opportunities.

Detroit's finish was brutal. They went 0 for 7 on high-danger chances and converted zero of seven rebound opportunities despite crashing the net relentlessly. Boston, by contrast, was ruthless: two goals from low-danger spots and three goals on rush chances (24 attempts). This is the margin in close games—execution trumps volume.

M. Geekie orchestrated the Bruins' depth with three assists in 14 minutes. C. McAvoy spent 27 minutes controlling play from the blueline (two assists). D. Pastrnak added a goal and assist in 21 minutes.

Khusnutdinov's wrist shot from the point (18:08, third period) marked Detroit's high-water mark. By then, Swayman had already closed the door.

The breakdown in twelve frames

Swipe it

Every number is from this page
Final · Mar 21
BOS
4
DET
2

J. Swayman stands tall as the Bruins edge the Red Wings

Chances 4.8 – 4.9Did they deserve it? →
Did they deserve it?

Dead even on chances. The Bruins took it anyway.

Expected goals · chance value
BOS
4.85
DET
4.91
50% of the chances50%

The board read BOS 4, DET 2. The chances read BOS 4.8, DET 4.9.

Our xG model · NHL play-by-play · all situations
Luck check
BOS
−0.8
goals above expected
BOS4.85 expected · 4 scored
Expected
Scored
DET4.91 expected · 2 scored
Expected
Scored

The Red Wings left 2.9 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. P2 03:35DETL. RaymondPP0–1
  2. P2 05:07BOSD. PastrnakPP1–1
  3. P3 04:06DETA. DeBrincat1–2
  4. P3 06:22BOSE. Lindholm2–2
  5. P3 09:42BOSN. Zadorov3–2
  6. P3 18:08BOSM. KhusnutdinovEN4–2
NHL play-by-play · chance value from our xG model
Where the shots came from
BOS
39 shots
4
Final
95 shots
DET
56 shots
2
BOS attackDET attack
BOS DET Goal
39
shots · 4 in
56
shots · 2 in
Every unblocked shot · press play to replay it
Chances by danger
BOSDET
1 / 7
2.69 xG
High danger
0 / 7
1.84 xG
1 / 15
1.74 xG
Medium
1 / 20
2.35 xG
2 / 30
0.43 xG
Low
1 / 41
0.72 xG

The Red Wings went 0 for 7 from the slot.

Danger tiers by our xG model · high ≥ 20% chance
In the net
A+
J. Swayman
+2.9
BOS · 42/44
A
J. Gibson
+1.9
DET · 23/26
The numbers, checked
BACKCHECK

J. Swayman stands tall as the Bruins edge the Red Wings

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 10–10no goals
    2ndshots 10–11
    1. 03:35DETL. Raymondpower play(A. Copp, P. Kane)0–1
    2. 05:07BOSD. Pastrnakpower play(C. McAvoy, M. Geekie)1–1
    3rdshots 7–23
    1. 04:06DETA. DeBrincat(M. Seider)1–2
    2. 06:22BOSE. Lindholm(M. Geekie, M. Lohrei)2–2
    3. 09:42BOSN. Zadorov(M. Geekie, C. McAvoy)3–2
    4. 18:08BOSM. Khusnutdinovempty net(D. Pastrnak, E. Lindholm)4–2

    score reads BOS–DET

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

    The numbers

    XGBoost xG · NHL play-by-play
    4.85
    BOS chances
    Goals their shots were worth
    −0.8
    Finishing
    Goals below what those chances were worth
    1.048
    BOS puck luck
    Above 1.000 — the bounces went their way
    43.3%
    Shot attempts
    Under half — they were outshot
    Split by club

    Who controlled the game

    4.85Expected goals4.91
    DET 50% of the chance quality
    27Shots on goal44
    7High-danger chances7
    52All attempts (Corsi)68
    Adjusted for score: BOS 43% · DET 57%
    Faceoffs · DET won77%off35%neu58%def
    Source · NHL play-by-play · XGBoost xG
    How the game was won

    The danger ladder

    shotsgoalsexpected
    High dangerslot & crease
    BOS1 / 7 · 2.69 xG
    DET0 / 7 · 1.84 xG
    Medium dangermid-range
    BOS1 / 15 · 1.74 xG
    DET1 / 20 · 2.35 xG
    Low dangerperimeter & point
    BOS2 / 30 · 0.43 xG
    DET1 / 41 · 0.72 xG

    DET went 0-for-7 from high danger on 1.84 expected goals — 1.8 left on the table.

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

    Finishing vs expected

    expectedactual
    BOS
    4 G · 4.85 xG · -0.8
    DET
    2 G · 4.91 xG · -2.9
    0123456

    BOS finished -0.8 against expected, DET -2.9.

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

    Shot diet

    goalsshots
    BOS
    WRIST3/18
    SLAP1/8
    SNAP0/5
    TIP IN0/3
    BACKHAND0/2
    DEFLECTED0/2
    POKE0/1
    OTHER0/13
    DET
    WRIST0/21
    SLAP0/13
    SNAP2/11
    TIP IN0/6
    BACKHAND0/3
    DEFLECTED0/2
    POKE0/0
    OTHER0/12
    BOS
    DET
    Off the rush
    3 G on 24
    2.35 xG
    1 G on 32
    2.62 xG
    Off rebounds
    0 G on 3
    0.93 xG
    0 G on 7
    1.18 xG

    Wrist shots carried the volume: BOS went 3-for-18, DET 0-for-21. BOS scored 3 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. Swayman
    BOS · 42/44 · .955
    +2.9
    saved above expected
    A+
    the night
    By dangerG/attxGsaved
    High danger0/71.8+1.8
    Medium1/202.4+1.4
    Low1/410.7-0.3

    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

    J. Gibson
    DET · 23/26 · .885
    +1.9
    saved above expected
    A
    the night
    By dangerG/attxGsaved
    High danger1/72.7+1.7
    Medium1/151.7+0.7
    Low2/300.4-1.6

    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

    95 shots · press play to watch the game back

    Where the shots came from

    NHL play-by-play coordinates
    BOS
    39 shots
    4
    Final
    95 shots
    DET
    56 shots
    2
    BOS attackDET attack
    BOS DET Goal

    Each club shoots toward its own end — BOS left, DET 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
    M. Geekie
    #39 · C · BOS
    0 G · 3 A · 1 SOG · 14:07 on ice · +2
    C. McAvoy
    #73 · D · BOS
    0 G · 2 A · 1 SOG · 27:05 on ice · +2
    D. Pastrnak
    #88 · R · BOS
    1 G · 1 A · 2 SOG · 21:27 on ice · +2
    Ranked from the box score — points first · Backcheck
    What the model said beforehand

    Before the game

    Written Sat, Mar 21
    Open the pre-game read
    Written from the numbers

    The read

    Edited for clarity
    ◆ By the ModelJul 12, 8:19 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 2.4–2.6 goal range with Detroit at 54% win probability—as close to a pick'em as projections get.

    Both teams operate on statistical knife edges. Corsi figures are matched at 49.0% for both teams, indicating equal positioning. Expected goals lean Detroit's way: 49.0% to Boston's 47.0%, a modest but meaningful advantage. Where Boston stands out is finish: its 1.023 PDO signals a team running hot through unsustainable shooting luck. Detroit's 0.985 PDO works the other direction, indicating suppressed finishing despite similar volume.

    The Bruins' outlier luck is the real story. That 1.023 PDO isn't sustainable; regression will come. Until it does, they get credit for a team that looks better than its process.

    For Boston, Viktor Arvidsson anchors the attack with 1.04 expected goals per 60 minutes and 18 goals to show for it. He's shooting at 13.0%—well above sustainable rates—and has recorded two high-danger goals. Tanner Jeannot contributes at 0.75 xG/60 with six goals, though his 8.3% shooting suggests room to run. Elias Lindholm represents Boston's defensive liability, a seam Detroit can exploit. The Bruins' 0% conversion rates on both high-danger and rebound opportunities compound the problem.

    Detroit counters with Alex DeBrincat, whose 0.88 xG/60 produces 17 goals on a 9.0% clip—sustainable and dangerous. Marco Kasper adds seven goals at 0.81 xG/60, though his 6.1% shooting leaves room to grow. Axel Sandin-Pellikka is a weak link in the lineup, another seam for Boston to attack. The Red Wings' matching 0% rates on high-danger and rebound conversions mirror Boston's vulnerability.

    The margin is thin: Boston's PDO advantage is a ticking clock. Detroit's better underlying metrics are a legitimate long-term edge. In one game, luck decides.

    What the model said beforehand

    The model's lean

    DET 54%
    54%
    DET
    Model favorite
    46%
    54%
    BOS50DET

    DET by 8 points of win probability — a modest lean. Projected score BOS 2.4–2.6 DET; 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 →DET
    47.0%49.0%
    49.0%49.0%
    2.392.38
    2.672.50
    2.221.73
    1.822.07
    1.0230.985

    The season numbers split 3–3 — no clear process edge — and the luck row (1.023 vs 0.985) 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
    +2 GD · 2d rest
    DET
    4-4-2
    -1 GD · 2d rest
    1.023
    BOS PDO
    Luck gauge · drifts to 1.000
    0.985
    DET PDO
    Luck gauge · drifts to 1.000
    What decides it

    Keys to the game

    Regression watch
    • The Bruins' PDO is 1.023 — running hot, expect some regression.
    Things to watch
    • 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
    2 days rest.958 last start
    Backup Jeremy Swayman · +28.8 GSAx this season

    No completed game on file for this club yet.

    DET
    Expected in goal
    J. Gibson
    2 days rest.970 last start
    Backup John Gibson · +11.7 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
    DET
    Alex DeBrincat17G 28A
    0.88 xG/60 · 2 HD · 9.0% sh
    Marco Kasper7G 8A
    0.81 xG/60 · 1 HD · 6.1% sh
    Keep going

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