by A month into the NHL regular season, front offices are beginning to get a sense of the quality and true talent level of the rosters they are putting together. As more games are played, trust—both ways—increases.
But the NHL is moving at lightning speed, and front offices (and the coaching staff, for that matter) have to make decisions with the limited data or video at their disposal.
Consider the situations in markets like Ottawa (4-8-0), St. Louis (3-8-0) and Columbus (3-9-0) – three teams with different expectations but three markets where the heat is on come here The expectations are real, and so is the pressure to deliver. Do the front offices sit idly by and hope the roster they’ve assembled can break out of a rut, or do they make changes early in the season in hopes of stabilizing the ship?
One of the most important data points to consider at this point in the season in terms of a team’s win-loss record – which can lie to you both ways so early – concerns the goalkeeping arena. Position is already volatile, and over a 12-game sample, performance can be as random as flipping a coin.
Over- or under-performing over the course of a month can drastically change our understanding of a team’s true talent level over the long term – goalies who run hot can gloss over mediocre results, just as goalies who run cold can hurt otherwise productive teams.
At this point in the season, I want to see how much influence the goalkeepers have on the 32 teams. First, let’s look at the goalkeeping landscape this season. The table below gives us the goal-scoring frequencies for each team, as well as how they use their goalies from a usage perspective. Most teams have only clothed two goalies, with five teams (Columbus, Chicago, Ottawa, Seattle, and Toronto) using three; Chicago is the only team to date to field more than three.
(Note: Penalty goals conceded are excluded in the table below.)
Teams like the Anaheim Ducks (64 clean sheets) and Vancouver Canucks (57 clean sheets) were extraordinarily generous on defense, while the Philadelphia Flyers (29 clean sheets) and Winnipeg Jets (28 clean sheets) were much more difficult to crack. But goals versus numbers measure all defensive performance, including goalies. What we need to do is understand how much goalkeepers specifically contribute to that number; Sometimes great goalies are killed by bad defenses in the front line, just as great defenses can be burned by bad goalies.
If we look at the expected goals conceded based on both the shot strength of each goalkeeper and the probability of each of those shots hitting the net, we can better understand how goalkeepers influence their team’s position in the standings.
Which teams are supported by their goalkeepers and which teams are sunk in the net by poor play?
The right column shows how many goals were deleted (or added) in the Goals Against column after we isolated goalie performance. You can see that there are dramatic changes in some cities.
On the other hand, the Flyers (+18 saved goals), the New York Islanders (+12 saved goals) and the Jets (+11 saved goals) in their group have produced incredible goaltending performances early in the season that have boosted them overall . The Flyers in particular are intriguing – Carter Hart is a viable preseason Vezina Trophy contender, and HockeyViz’s coverage of what’s going on in the Philadelphia defensive zone is his strongest argument:
At the other end of the spectrum, you have teams like the Columbus Blue Jackets and Canucks, who had a holey goaltendership earlier in the year. In Vancouver you have a goalkeeper in Thatcher Demko who has an excellent track record up to this season – in other words, the type of player you’d expect to break out of a rut, and fast.
That’s unlike a team like Columbus, which is 13 goals worse than expected, dead last in the NHL. Elvis Merzlikins and Joonas Korpisalo have struggled in recent years, giving up goals from all areas of the defensive zone more often than their average league counterparts (via HockeyViz):
There are never easy answers when it comes to goalies, but for front offices trying to gauge how well-performing their lineup is compared to the rest of the league, understanding their contribution to the table is imperative.
A misinterpretation of how much – or how little – a goalkeeper affects a team’s performance can lead to panicked squad changes or over-confidence, which doesn’t end well in the long run.
Data via Natural Stat Trick, NHL.com, Evolving Hockey, Hockey Reference
#Preseason #NHL #Goalies #TSNca
