If you’re a member of the Corsi brigade, the first round of these playoffs were likely tough on your morale. The better regular season Corsi team won just two of the eight first round playoff match-ups and the team that won the possession battle in those series went on to win just three of the series. Combine that with Calgary making it (and winning a round, too) over Los Angeles and it was a rough April for the calculator crowd. It was enough for some people to outright render all stats meaningless in the playoffs. A seven-game series of playoff hockey breeds chaos; anything can happen and the numbers don’t matter. Except that’s only half true. The games may be chaotic, but the numbers still matter. Despite what the critics may say, puck possession is still very important in a short series. The first round may have been unpredictable by shot metrics, but that was a bit of an anomaly compared to recent years. The second round has seen a giant market correction as the four better regular season possession teams all have a stranglehold in their respective series.
Ultimately, the hockey gods will decide which way the dice land, but if you have the puck more than the other guys the dice are loaded in your favor. Sometimes it doesn’t matter. Sometimes the better team doesn’t win. But more often than not, having the puck and getting the most shots on net usually leads to winning amidst all the chaos. Considering how close each team is in talent and how close playoff games are that should make sense. If the playoffs are chaotic, controlling the game means controlling the chaos. Each extra shot attempt increases the chances that one of them will go in, and if you’re the team taking the attempts it means the other team isn’t. All it takes is one bounce and having the puck means getting more chances to cash in on that bounce. Since 2007-08 – not including this year – the team that won the possession battle in the series won 65 percent of their respective series, and their chances of winning went up the higher the possession advantage was. Puck possession is something that usually comes through in the long run, but even in the small sample of four to seven games it holds up as a big advantage over the other team. Looking at the teams that won a Cup in those seasons and their score-adjusted unblocked shot attempt percentage during the playoffs seems to prove that notion. All seven controlled the lion’s share of possession over the entire playoffs and of the 28 series they were involved in, only four times were they out-possessed by the other team. Two of those were a Boston team riding one of the best playoff goalie performances ever with Tim Thomas.
The big takeaway here (other than how insane Detroit was back when puck possession hockey was their little secret) is that when the games get closer and tighter in the playoffs, the best teams win by controlling the game. In the regular season, Tampa Bay and Washington were the better possession clubs than Montreal and the New York Rangers, but the Lightning and Capitals are leading their respective matchups. This year, the teams leading the charge are Anaheim and Chicago. They’re the only teams left who have controlled play in both of their first two series. Considering how the other Cup teams played, they’re likely the best bets right now. Even though this year’s playoffs started strange for the math enthusiasts, it likely won’t continue. Generate more shots than the other guys and the wins will come. It’s not the only way to win, and it’s not even the only reason past Cup-winning teams won, but it’s an edge over other teams when the margins are razor thin.