Wednesday, February 4, 2009

Playoff Performance

Hockey analyst James Benesh was kind enough to give me a complete copy of all playoff save percentages since 1952 recently, which allows me to update some of the playoff numbers that I began here as part of a larger look at save percentages.

One thing I didn't like about my previous method was comparing against the average playoff save percentage each season. This because the average will be influenced by the teams that advance deep into the playoffs. For example, the 1985 playoffs had an average save percentage of .882, in large part because the Oilers destroyed everyone. In 1986 the Oilers were upset, less high-scoring teams went to the Finals, and the average playoff save percentage rose to .895. For teams that went out in the first round and never had to play the Oilers or Habs, the context likely wasn't all that different, so it doesn't make tons of sense to me to adjust for it. Another factor is that a goalie who goes to the Stanley Cup Finals makes up quite a large part of the average. Goalies can face one-sixth or more of the total shots in an individual playoff season, so this means that an outstanding season is probably understated when compared to league average, since the goalie is at least in part being compared to himself.

My post about the advantage of goalies never having to face their own All-Star shooters suggested adjusting for each goalie's competition as well. I ended up making both an era adjustment and an opponent adjustment. The era adjustment was based on the average shooting percentage of all teams that qualified for the playoffs that season. The opponent adjustment was based on the regular season shooting percentage of all opponents faced in each playoff season for any given team.

A couple of other points: Since I need shot data for the adjustments, I am limited to the period from 1968-2008. Also, the adjustments are made from total number of games played by the team in the playoffs. For teams that platooned their goalies, the adjustment will not be exactly correct. It is not possible to be more accurate for many of these seasons as I have no way of finding out which goalies played in which game. I don't think it would have much of an impact over the course of a career, but if there was for example a case where one goalie played the first round against Winnipeg and another one played the second round against Edmonton, the adjustment would be a bit unfair.

Here are the results for goalies with at least 60 games played in the playoffs. ("LgAvg Sh%" is the shooting percentage of the average playoff team throughout the goalie's career to show the era they played in, while "Adj Opp Sh%" is the era-adjusted opponent shooting percentage for the opponents faced by the goalie's team in each of their playoff seasons).

RankGoalieLgAvg Sh%Adj Opp Sh%Career Sv%Adj Sv%
1.John Vanbiesbrouck11.5%12.3%.915.922
2.Dominik Hasek10.2%11.9%.925.919
3.Ken Dryden11.3%12.0%.915.918
4.Bernie Parent11.2%11.7%.917.917
5.Billy Smith12.7%11.8%.905.917
6.Patrick Roy11.1%11.5%.918.916
7.Ed Belfour10.5%11.5%.920.914
8.Kirk McLean11.4%12.0%.907.911
8.Martin Brodeur10.2%11.6%.919.911
8.Grant Fuhr12.0%11.8%.903.911
11.Mike Richter11.0%11.9%.909.909
11.Curtis Joseph10.4%11.4%.917.909
13.Chris Osgood10.1%12.1%.914.908
14.Tony Esposito11.3%12.0%.903.907
15.Felix Potvin11.1%11.3%.910.906
16.Tom Barrasso11.4%11.5%.902.903
17.Kelly Hrudey12.2%11.9%.891.902
18.Ron Hextall11.6%11.6%.897.900
18.Mike Vernon11.5%11.8%.896.900
18.Jon Casey11.5%11.9%.895.900
18.Gerry Cheevers10.8%11.8%.902.900
22.Andy Moog12.0%11.8%.890.899
23.Mike Liut12.8%11.2%.888.898
23.Don Beaupre12.3%11.8%.886.898
25.Pete Peeters12.7%11.6%.881.895
26.Ed Giacomin10.4%12.4%.895.894

This does not take into account quality of team defence. Some of these goalies no doubt had a much easier job than others. In fact, most of the top 10 probably had the advantage of playing on strong defensive teams. I would expect that Dryden, Parent, Smith, Roy, Belfour, and Brodeur faced easier than average shot quality against. Having said that they did finish in the top 10, ahead of some other guys who also played for strong teams, which implies their performances were likely above average.

Take Billy Smith, for instance. There is lots of evidence that the Islanders allowed easier than average shot quality against (the defensive talent on the team, the observation that Smith's playing partner usually posted better regular season stats, and the fact that Smith's main playing partner, Chico Resch, had a .919 adjusted playoff save percentage). However, even if Smith faced shots that were 10% easier than average, which is the typical high range of what we see in modern hockey during the regular season, he would still show up at .908 which is just outside of the top 10. The caveat is that if there was one goalie who had a shot quality adjustment far outside the norm I would expect it to be Smith, given that he played the large majority of his playoff games in a 5 year stretch when his excellent two-way team dominated the rest of the league in the playoffs.

Two of the biggest surprises are John Vanbiesbrouck and Kirk McLean. Each of them had one long playoff run that contributes to their strong numbers. It looks like Vanbiesbrouck also played well outside of Florida, he just kept running into better teams. Vanbiesbrouck's 12.3% adjusted opponent shooting percentage was the second highest on the list.

Near the bottom of the list are two Hall of Famers, Gerry Cheevers and Ed Giacomin. Since Cheevers was inducted on the grounds of his playoff performance in Boston, these results suggest that he was mostly carried by his teammates and was not a great goaltender. If you do a similar adjustment to shots against per game (i.e. adjust for era and opposition), Cheevers ranks #2 of all 26 goalies in fewest shots against. If you want to know who finished #1, the title of this blog will give you a clue.

Giacomin is another guy that I don't think is deserving of the Hall of Fame. He had a few good years in New York on a strong Rangers team, but after that his career fizzled and he was outplayed by his teammates more often than not. In the playoffs, Giacomin's record is very poor. The numbers show that he faced the strongest opposition of any of the goalies, but even taking that into account he finished dead last in save percentage.

I had a debate about Tony Esposito a while back where we ended up concluding that Esposito's playoff performance was probably subpar. These results suggest Esposito was actually about average, with a .907 adjusted save percentage. If Esposito was a choker, what does that make Ed Giacomin with his .894?

Looking at the goalies who played in less than 60 games, there were a couple of interesting results. Mike Palmateer did very well, with a .919 adjusted save percentage. Gilles Meloche, a goalie who was constantly limited by the abilities of his teammates, came in tied with Esposito at .907, which is a pretty decent result.

For current goalies, Kolzig (.922), Giguere (.916), Lalime (.913), Kiprusoff (.912), and Khabibulin (.911) have good records, Nabokov's is fairly ordinary (.905), and Theodore (.897) and Turco (.897) fared worse. As always, be sure to keep team factors in mind when interpreting those results.

5 comments:

The Puck Stops Here said...

The question is sample size. Many of these goalies only had one or two deep runs into the playoffs in their careers. Is that really enough to make a meaningful judgement?

seventieslord said...

What do you need? 200 playoff games? 300? He only chose goalies with 60+ playoff games, which means they were spread out over a minimum of three seasons.

If these are the largest sample sizes available among these goalies, doesn't that make them large enough sample sizes?

Anonymous said...

another incredibly faulty and highly suspect ranking dependent solely upon save percentage. go figure.

Anonymous said...

Character,loyalty,and simply the BEST to have stood between the pipe. Just say NO..........

Host PPH said...

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