Kings Sharks Playoff Preview: Goaltending

To wrap up Jewels from the Crown's Kings-Sharks preview (check out previous installments on zone entries, even strength play and special teams), we'll take a look at goaltending. The Sharks have maintained the possibility that Alex Stalock will start game 1, but I'd be stunned if Antti Niemi was not the starter. We do know for sure that Jonathan Quick will be starting in goal for LA. We'll only be using save percentage and its derivatives to analyze these goaltenders, since both wins and goals against average are team-dependent stats useless for evaluating goaltenders.

First, a look at their career numbers:

Quick and Niemi Career Comparison

Career Regular Season SA Career Regular Season SV% Career Playoff SA Career Playoff SV% Career Total SA Career Total SV%
Jonathan Quick 8755 0.915 1466 0.929 10221 0.917
Antti Niemi 7526 0.916 1632 0.909 9158 0.915

You can get into trouble comparing goaltenders by raw career SV% like this, because doing so will underrate goalies like Ryan Miller who have played significant chunks of their career in seasons with much lower league-average save percentages. Quick and Niemi have been in the league for essentially the same time, so that's not an issue.

Obviously, these two are extremely close. Quick's much higher playoff SV% stands out, but I would not read much into that. Neither goalie has faced enough postseason shots for that stat to be reliable. Even after 3,000 shots a goalie's save percentage is about half talent and half luck, and Quick and Niemi are both around half that number in the postseason. We can predict future playoff performance more accurately by looking at career performance.

However, I do not advocate discarding the playoff data. It adds significantly to the sample size of both goalies, and in the case of Jonathan Quick it actually makes a difference. There is no compelling reason I can see not to combine the data and get the biggest sample size we possibly can. So Quick ends up as a bit of an odd case, as people who focus on regular season data will slightly underrate him, and people who focus on postseason data will vastly overrate him (maybe even to the point of giving him a $58 million contract).

Anyway, these two are both above average goaltenders, with a slight edge to Jonathan Quick.

Since Quick and Niemi have probably changed quite a bit over their careers, it's worth taking a look at just this season, even if that means drastically reducing our sample size:

Quick and Niemi 2013-14

Even Strength SA Even Strength SV% Penalty Kill SA Penalty Kill SV% Total SA Total SV%
Jonathan Quick 928 0.929 217 0.862 1183 0.915
Antti Niemi 1439 0.919 216 0.861 1705 0.913

Both goalies have had okay years, with Quick again being slightly better. I wouldn't read a ton into this data, again because of sample size issues (especially in the case of Quick, who didn't play a full season).

Looking at raw SV% makes Niemi seem much closer to Quick than he has been, because a much higher percentage of Quick's shots against came on the PK (18.3% for Quick vs. 12.7% for Niemi). This a result both of LA taking a lot more penalties than San Jose and LA's penalty kill not being as good at suppressing shots. If both goalies had faced a league average % of PK shots (15.9%), stopping all shots at the above rates, Quick would be around .917, Niemi around .911.

In addition to having a slightly stronger season, Quick has been better than Niemi down the stretch (.920 SV% over the last ten games for Quick, .896 for Niemi). I would put zero stock in that. Goaltender performance naturally fluctuates tremendously over such tiny samples, as this classic piece demonstrates.

If the Sharks fail to grasp that concept they might start Alex Stalock, owner of a sparkling .932 SV% this season. That's come over only 571 shots, and Stalock has a much larger track record of AHL mediocrity (.909 over 4004 shots). It's possible that Stalock has taken a huge leap forward, but it's far more likely that he's just another mediocre goaltender having a fluky run of success. If the Sharks turn to Stalock this series for whatever reason, that's great news for the Kings.

Martin Jones won't be significant in this series unless something goes horribly wrong. He does have a good AHL track record (.919 over 3894 shots) to go along with his small-sample NHL success, suggesting that he is probably the much better backup goalie.

The Kings' biggest advantage in this playoff series is their dominance at even strength. They probably do have an edge in net but only a very small one. That may be a disappointing conclusion for Kings fans who vividly remember Quick's brilliant postseason play, but the reality is both goaltenders are very solid. Quick probably is a tiny bit better though, and with these teams so evenly matched every little advantage matters.