There has been a lot of chatter lately about what kind of goaltender Devan Dubnyk is — is he a number one goalie, is goaltending a weak spot for the Oilers, does he look like a giraffe, etc. What I’d like to do is place his recent performance into historical context, and attempt to predict where his career trajectory might be headed.
Firstly, let’s establish the empirical basis for this post: over the last two seasons, Dubnyk has managed to post a save percentage (SV%) above the league average while playing at least 35 games. This may not sound like much, but it’s actually quite an accomplishment — goalie SV% has a tendency to deviate wildly above and below league average, which makes forecasting future performance incredibly tricky. My hypothesis is that goalies who post an increasing number of consecutive seasons above league average while playing (a pro-rated) at least 35 games in a season provide a key measure in deducing their true quality.
Now, we’ve got to establish what league average save percentage is. To do this, I downloaded each season’s full list of goalies from hockey-reference.com, and then added up all goals scored and all shots against them. That particular site has data back to 1983-84, and I was able to grab one more (82-83) from NHL.com. Before that, SV% as a reliable statistic ceases to exist. As you can guess, league average SV% has been steadily increasing:
You can see why basing these stats relative to each year’s save percentage is important — in the 80s, posting a SV% of 0.900 or higher was very rare, while posting that mark today might get you placed on waivers (unless you’re Miikka Kiprusoff). There was a massive jump up in SV% after the 1994 lockout, which is why so much of my analysis on this site uses 1994 as a historical cutoff for analysis. Today goaltenders are the most effective they’ve ever been at stopping the puck.
Let’s have a look at the list of goaltenders who’ve posted at least 2 consecutive years of league average or better SV% while playing the equivalent of 35 games in a season. I picked 35 games as that’s a mark you would have to play to be, at the very least, considered an integral part of a tandem. It also helps to decrease the randomness of hot streaks, etc.
If this graphic is too small, click through to enlarge it in a separate tab. Players in yellow are harbouring current streaks, while underlined players are merely active players who had streaks in the past.
What does this tell us? Well, Patrick Roy played 18 consecutive seasons above league average, and the Beezer is one of the most underrated goalies of all-time. But it also tells us that posting above league average SV% in consecutive seasons is an incredibly rare feat, especially when you start posting 5 or more. Even goalies who are considered some of the best in the world tend to post seasons below average in the middle of seasons above average. See, for instance, Mike Richter, who was only able to post two different two season streaks of above average play. Kiprusoff was considered an elite goaltender for much of the last decade, but was only ever able to string 3 consecutive seasons of above average play in a row. Even over the large sample size of an entire season, the randomness of goaltending makes it very hard for even the best goalies to sustain average play.
Dubnyk is one of 12 NHL goaltenders who currently have streaks underway. Notice goaltenders who do not currently have streaks of above average play who are considered in the elite of the NHL: Marc-Andre Fleury, Martin Brodeur, Kipper. Also notice goalies on this list who are severely underrecognized for their play — Luongo, Vokoun, Niemi, and yes, Dubnyk.
Out of 163 distinct goalies who’ve posted an above average season (and 551 above average goalie seasons), only 86 different goalies have managed to string two together in a row. Only 56 have managed to string 3 in a row together. Dubnyk has proven that he is not a one-hit wonder in the NHL by putting 2 quality seasons together. The mainstream media talk about Dubnyk being a question mark is overblown, and I think these numbers show it. But some will complain that there are a lot of “2 and out” goalies on the list above — 2 straight good seasons doesn’t guarantee a good career. So let’s test it out. I compiled a list of all goaltenders who posted two consecutive quality seasons by the time they were 27 years old and played at least 35 games in the season after the two-year streak to see how they did in that season afterwards. Here’s a list:
These numbers are expressed as a differential to the league average save percentage in whichever year they posted their streaks. The entire idea is to see if Season 3 is able to show some kind of consistency in results — did the 2-year streak goaltenders stay above league average (greater than zero), or did they slip to below league average (less than zero). Here’s a handy summary:
So exactly two-thirds of goalies with a two-year streak before the age of 27 were able to again post an above-average season in the next year. I know you probably thought the trend was going to be higher, but you’re going to have to trust me that in the world of goalie stats, this is a pretty suggestive trend of sustained-quality. The average SV% differential compared to league average in the 3rd season was 0.004… suggesting that a goalie like Dubnyk who posted bang-on the average last year of 0.914 could stand to post a 0.918 this year. My prediction before the season started was 0.920 or higher, and the early returns suggest he’s well on his way to posting an above average season in 2013.
Is Dubnyk a legitimate starter in the NHL? Yes, of course, and stop listening to whichever fool suggested he wasn’t in the first place.
As an aside — would you like to see the list of historical goalie streaks that were 0.010 ABOVE the league average SV%? YES????? ok check this out:
Only Henrik Lundqvist currently has a streak going that’s 0.010 above the league average, and he’s in some heady company. Notice who’s not on this list? Grant Fuhr. And I have another post in the hopper about showing who the most overrated goalies of all time are that he may or may not be featured in…
So, what are the most dominant goalie seasons of all time relative to league average save percentage?
Here’s a list of all goalie seasons that were 0.025% above the league average (so, if the league average was 0.900, you’d have to post 0.925 to get on this list). Out of the 22 such seasons in history, Hasek has 5, and Roy has 3 — meaning they account for over a third of such seasons by themselves.
I said it on twitter yesterday — Hasek is the Gretzky of goaltenders, and I consider him a top 10 hockey player of all-time. This analysis should help tell you why.