In hockey circles in recent years, there is one word that has worked its way into the minds of hockey fans as a word you do not want to hear when your team is doing something well. There is just one word that will unsettle confident supporters to the point where they will feel the need to defend their team in the face of all logic and rational evidence. That word is regression. You've heard it. You've seen the 2013-2014 Toronto Maple Leafs defy possession metrics for two thirds of the season only to come crashing back down to earth while missing the playoffs in spectacular fashion. You read when Steve Simmons and others were certain that the Maple Leafs had the necessary intangibles to sustain poor performance while salvaging winning results. But like the 2011-2012 Minnesota Wild, the 2012-2013 Maple Leafs, the 2013-2014 Colorado Avalanche, and numerous other teams before them, the fate of the 2013-2014 Maple Leafs would either have been missing the playoffs altogether or drastically underperform once they got there.
Regression is a cruel mistress with which fortunate teams will unwillingly be forced to test their fate. Like a police car tucked away on I-540 in the dark of the night waiting to pull over speeding motorists, regression is the force in hockey which oversees all and does what it can to ensure that every team and player will stay within the conventions of the game over a large enough sample size.
While we haven't seen anything so dramatic with our Carolina Hurricanes, there is no doubt that we have watched one aspect of our team's game regress over the course of the last few weeks. What was once the league's best penalty kill has now been shrunk back down to size. With the departures of Andrej Sekera and Tim Gleason, some level of decreased play while shorthanded was to be expected, but not necessarily to the degree at which we have seen it.
When it comes to penalty killing, there are two main factors that make a team successful or poor. One is shot suppression. Shot suppression on the penalty kill essentially boils down to the positioning of the players a team deploys while shorthanded, their aggressiveness in attacking the points, their ability discern when to crowd the net and make it difficult to get shots in close, and the defensive skills of the penalty killers the team is using. The other main factor in penalty killing success is goaltending. How good your goaltender is at stopping shots while shorthanded is crucial to maintaining a top penalty kill. You could have a shorthanded unit of, say, Zdeno Chara, Shea Weber, Patrice Bergeron, and Jonathan Toews, and if the goalie you put behind them was turning in an .800 SV% they would still be one of the worst penalty kills in the league.
So it seems simple, right? Teams with the best goaltending should usually have the best penalty kills. But it isn't always that simple. For example, Montreal's Carey Price is having what is most likely the best goaltending season in a very long time. Montreal ranks 3rd in the league in on-ice shorthanded save percentage, but because their penalty kill allows a high volume of shots on a consistent basis, they are only 7th in the league in penalty killing percentage. Some elite goalies sometimes can have off years in penalty killing situations. Nashville's Pekka Rinne, the de facto runner up to Price for this year's Vezina award, has led Nashville to a rank of 22nd in penalty killing save percentage. The reason for this is that in many cases, goaltending ability on the penalty kill is not a repeatable skill. The sample size, even over a full season, is too small and is therefore liable to significant variance. This is why shot suppression (in all situations really, but specifically on the penalty kill) is so important. It is a repeatable skill to be able to be good defensively and limit the quantity and sometimes quality of the shots that opposing powerplays get through to your goalie.
In Carolina's case, the recent regression of the penalty kill really is not too much of a cause for concern. While the team was 1st in the league in penalty killing percentage for a long stretch, they were never the clear best team in terms of shot suppression while shorthanded. What caused Carolina's absurd penalty killing success was a combination of top five shot suppression and top five shorthanded goaltending. Cam Ward, despite having a nice rebound season, should not be expected to maintain a top five shorthanded save percentage, as he did for much of the season until recently.
To understand who or what specifically has made the Hurricanes penalty killing so successful this season, let's take a look at the Hurricanes' league wide ranks in terms of shorthanded shot suppression and save percentage, and then take a look at the individuals who are most responsible for pulling the unit in the right direction.
It all checks out pretty well. The Hurricanes have consistently ranked in the top four all year in shot attempts, unblocked shot attempts, and shots on goal against per 60 minutes on the PK. That has not changed, despite the losses of Andrej Sekera and Tim Gleason and the inclusion of less experienced, younger defensemen as a necessity due to those trades.This suggests a couple of things. That the penalty killing system concocted by Steve Smith and Bill Peters is very effective in terms of shot suppression and outperforming what one would expect in that regard based on the available personnel (this is also true at even strength). What it also tells us is that the forwards employed by the 'Canes on the penalty kill (Jay McClement, Pat Dwyer, Nathan Gerbe, and Riley Nash) are very, very good at what they do.
So if the ability to suppress shots hasn't diminished, what has? Why did the Hurricanes go from owning the league's best penalty kill to only the fifth best in a matter of weeks? The simple answer is that Cam Ward's play when down a man has fallen off. And that's really no knock against him. He has rebounded to close to league average this year after a miserable go last season, and he deserves credit for that. At one point, he was 5th in the league in shorthanded save percentage. Now? He sits at 26th.He is, however, nowhere near the top five in the league's goalies in terms of even strength save percentage, so why would we expect him to suddenly become elite when the team is shorthanded? We wouldn't, no reasonable team would. Is it possible that some of Ward's decline has been due to a higher quality of shots faced since players like Gleason and Sekera have departed? Maybe, but it's unlikely. If the quality of defense had really declined that much, we would have seen both the quality and the quantity of shots increase, but the quantity has remained consistent. Further against this idea is the fact that Anton Khudobin has held on to the #7 slot in the league in SHSV%.
So yes, Cam Ward's play while shorthanded has regressed. With it, so too has the team's rank in league wide penalty killing percentage. But realistically, this is something that could be seen coming. Remember, regression waits for nobody. It doesn't care what players you like or what team you like. That's just the nature of the beast, but none of this is to say that the 'Canes penalty killing has been a mirage. The fact that they rank in the top four in each of the three categories of shot suppression dictates that they should expect their penalty kill to fall within the top four assuming equal goaltending across the league. Even if Ward and Khudobin find themselves in the 15-20 range in SHSV% next season, if the excellent shot suppression ability displayed this season carries over to next year, the team's penalty kill will be comfortably within the league's top ten.