Who are these guys? Are we sure that these are really the 2009-10 Boston Bruins? Because it seems like something has changed over the past few weeks, turning a mediocre, bubble playoff team into the potential Eastern Conference representative to the Stanley Cup Finals. Or is it the other way around – that the best team in the Eastern Conference has finally regained their form from 2008-09 after a sleepy regular season?
Right – you remember the dominant regular season that Boston enjoyed last season – featuring promising young guns like Phil Kessel (20 years old), David Krejci (22 years old), Blake Wheeler (21 years old), Milan Lucic (20 years old), Patrice Bergeron (22 years old) and Dennis Wideman (25 years old) complementing an impressive veteran core featuring the likes of Vezina Trophy winner Tim Thomas, Norris trophy winner Zdeno Chara, All-Star Marc Savard and trade deadline acquisition Mark Recchi. Going into this season, it seemed a given that the second highest scoring team of 2008-09 (270 GF, 3.29 GF) would only get better in 2009-10 with the further maturation of this great collection of talent.
But it was already apparent by the time that the Winter Classic rolled around three months into the season––ironically pitting current playoff combatants Boston and Philadelphia––that something was amiss with last season’s high flying Bruins. It wasn’t just a few players disappointing, but a wholesale offensive swoon up and down the roster. By the time the regular season ended––with rookie netminder Tuukka Rask’s heroics rescuing the Bruins’ second season aspirations––Boston had mysteriously transmogrified into the lowest scoring team of 2009-10 (196 GF, 2.39 GF/game), even edging out the pitiful Edmonton Oilers for that ignominy.
What could possibly have happened, to derail a talented young team on the rise? Could the difference in scoring be as simple as trading away their top young forward––Phil Kessel––to the Maple Leafs, losing Marc Savard to injury for half the season and having the rest of the team’s scoring regress to the mean?
Let’s take a look at how the 2009-10 Bruins compare to the 2008-09 Bruins to see where some of the changes in performance occurred:
P/GP: Points per Game Played
OGVT: Goals Versus Threshold, Offense
Boston Bruins - What happened to their top offensive performers of 2008-09?
2008-09 2008-09 2009-10 2009-10 Change Change
Name Pos P/GP OGVT P/GP OGVT P/GP OGVT
Marc Savard C 1.07 14.7 0.80 4.6 -0.27 -10.1
David Krejci C 0.89 13.7 0.66 4.3 -0.23 -9.4
Phil Kessel RW 0.86 13.2 -- -- -0.86 -13.2
Zdeno Chara D 0.63 9.3 0.55 5.9 -0.08 -3.4
Dennis Wideman D 0.63 8.8 0.39 2.4 -0.24 -6.4
Michael Ryder RW 0.72 8.7 0.40 1.2 -0.31 -7.5
Mark Recchi RW 0.76 8.3 0.53 3.0 -0.23 -5.3
Blake Wheeler RW 0.56 6.8 0.46 1.3 -0.09 -5.5
Chuck Kobasew RW 0.62 6.7 0.14 -0.6 -0.47 -7.3
Milan Lucic LW 0.58 5.6 0.40 0.6 -0.18 -5.0
Matt Hunwick D 0.51 4.7 0.18 0.2 -0.33 -4.5
Patrice Bergeron C 0.61 3.3 0.71 5.3 +0.10 +2.0
Marco Sturm LW 0.68 2.6 0.49 3.2 -0.20 +0.6
Mark Stuart D 0.21 1.7 0.13 -0.9 -0.08 -2.6
Andrew Ference D 0.34 1.4 0.16 -1.2 -0.18 -2.6
Miroslav Satan RW -- -- 0.37 0.6 +0.37 +0.6
Average/Total 0.65 109.5 0.45 29.9 -0.21 -79.6
While the table above doesn’t include all of the Bruins’ players of the last two seasons, you can easily observe the overall collapse in production of their 2008-09 offensive core. Yes, the loss of Phil Kessel hurt, but most of the -79.6 OGVT loss accounted for here simply came from downturns in the performances of the rest of Boston’s key contributors. What could the possible explanations be?
As my colleagues Rob Vollman and Gabe Desjardins pointed out to me, you can start with exceptionally good luck turning into bad luck (“regression past the mean”, you might say). The Bruins’ team shooting percentage went from a reasonably typical 8.8% in 2007-08 to a very high 10.9% in 2008-09 to a low 7.5% in 2009-10. You can immediately see the impact on scoring: with the team taking 2,599 shots on goal to pot their 196 GF this season, a shooting percentage of 10.9% would have instead yielded 283 GF, back to the haughty levels of 2008-09.
What could have brought about such an uptick in shooting percentage? One factor is the “score effect”, as Tom Awad has described. Tom found that teams leading in a game typically shoot at a roughly 10.0% shooting percentage while teams that are trailing or tied shoot at a 8.5%-9.0% shooting percentage. Certainly the Bruins played from in front plenty, in what was a dominant 2008-09.
In any case, we have a partial answer: the success of last season’s Bruins on offense was largely a mirage. So what has driven Boston’s success in the first two rounds of the playoffs?
Looking over their relatively small sample of 11 playoff games, Boston’s GF/game has increased from 2.39 to 2.91, yet much of the gain has come from an unsustainable increase in power play percentage (16.6% to 23.7%) – with an assist to Buffalo’s suddenly inept penalty killing.
Boston Bruins - GF increase in playoffs (goals/game)
ES PP SH EN Total
Regular season 1.74 0.54 0.06 0.05 2.39
Playoffs 1.91 0.82 0.00 0.18 2.91
Change +0.17 +0.28 -0.06 +0.13 +0.52
Similarly, Boston has been fortunate in man advantage situations. As for the other side of the puck:
Boston Bruins - GA decrease in playoffs (goals/game)
ES PP SH EN Total
Regular season 1.68 0.45 0.04 0.04 2.33
Playoffs 2.45 0.27 0.00 0.09 2.82
Change +0.77 -0.18 -0.04 +0.05 +0.49
The Bruins have been lucky indeed to have only three power play goals against––and it was only two PPGA before their Game 5 loss––fueled by a highly unsustainable .944 save percentage in 4 vs 5 situations (which was .955 before Game 5). In comparison, Chicago is second at .922 among remaining teams, with San Jose third at .902; Boston’s .908 save percentage on 4 vs 5 situations during the regular season was actually above average. Though a good penalty killing team in the regular season at 86.4%, we knew their 95.0% PK rate wouldn’t last. We know that their 93.0% rate won’t last either.
Taking out empty net goals for and against, you’re looking at a team that’s gone an even 30 GF and 30 GA, versus injured (for example: Vanek, Hecht, Carter, Gagne, various Flyer goaltenders) and subsequently mediocre opposition in this playoff campaign. Give the Bruins credit for the physical play that turned the Sabres series around as well as their gritty resolve to come back from deficits, but Boston’s going to need to sweat it out just to salvage this Philadelphia series. Given power play and penalty killing rates that have been by far the most fortunate of any playoff team, in addition to the loss of this postseason’s MVP David Krejci, and much better opposition around the corner, and this ride starts to look like it can’t last much longer.
Timo Seppa runs the statistical hockey site Ice Hockey Metrics. Follow Timo on Twitter at @timoseppa.
Timo Seppa is an author of Hockey Prospectus.
You can contact Timo by clicking here or click here to see Timo's other articles.