It has been said that a “stay-at-home” defensive defenseman’s value expands in the post season. The theory behind this supposes that the looser rules regarding physical force and obstruction play into these defender’s strengths. However, this is not always the case.
Thus far, we have seen some of the larger names in the business struggle in their roles.
Figure 1. Key defensive defensemen 2014 post-season numbers for 5v5 situations
All of the players above are well respected by many members of the media and general public, but are posting poor Corsi% relative to their team. In addition, all of these players are highly respected by hockey management for the most part, as seen by the defenders impact on the salary cap.
Seven out of the nine defensemen are signed to contracts that average more than 3 million dollars a year. Of the two who are not, Andrew Macdonald will soon be receiving a raise to 5 million dollars average per a year and Jeff Schultz was originally set to be paid 3 million this season but was bought out due to Washington Capitals issues with getting under the salary cap. Plus, Dan Girardi is expecting a raise to 5.50 million dollars AAV. These players were not chosen to fill an agenda, but simply because their names stand out in the crowd and are well known.
Despite their defensive efforts, their teams are being outscored by a combined 47-69, a goal% of 40.5%, below that of even their combined Corsi%. Six out of nine of the teams have better goal differentials with the player off the ice than when the on. While some of these players took tough defensive assignments, not everyone did. In addition, some of the players with tough minutes still performed poorly relatively to normal expectations.
While some of these defenders may indeed be above average defensively, there is more to the game than simply playing well defensively. I have previously mentioned that observers often look for direct causation when evaluating a player defensively or offensively; however, we tend to miss the hundreds of indirect moments that add up in the game as well. These indirect moments cause the team to be pinned in their own zone more, and indirectly scored upon more. This should come to no surprise, as players with poor Corsi% tend to regress to poor goal%.
But what about regular season versus post-season? Is there a connection or no?
Figure 2: Player’s relative Corsi or goal percentage in regular season versus playoffs
The playoffs are a different breed, in the fact that you are most likely to face tougher possession teams on average than you would in the regular season. This is why relCorsi% is used, as facing a stronger team on average will most often affect all players relatively equally.
We see -as expected- that good Corsi players tend to better in the post-season than those who are not good, but there are exceptions. Some of these exceptions will come from the small sampling effects of the post season; there are skaters in the sample with only 4 games played while the regular season sample is 40+ games. In addition, there are likely usage effects at play as well, with players playing on different pairings and/or with different forward groups in front.
There is also another curious pattern.
Figure 2. Mean and standard deviation of post-season relCorsi, grouped by regular season relCorsi
It seems that the better regular season Corsi players were not just better on average, but the samples were far more consistent in their differences. What is really interesting is how suddenly the results differ above and below a zero relCorsi%.
The takeaway here is not that all defensive defensemen suck, because not all defensive players do, just as not all offensive players excel. There are some legitimate defensive players who can reduce the bleeding while taking the tough minutes. This is why they are labelled defensive defensemen. However, not everyone is like this. Some players are labelled defensively simply due to the absence of offensive production. In addition, it is also true the playoffs do not magically make such defensive players automatically better.