Friday, March 16, 2007

Playoff Clutch Performance

"Clutchness" is one of the hot topics of debate in the sports world, especially between traditionalists and sabermetricians. Is there evidence of clutch performers? It is difficult to say, although studies that deny such an effect have tended to be more convincing than ones that claim clutch players exist. The viewpoint here is that there are no clutch performers, merely clutch performances, but when we are grading goalies based on their playoff performance, then those clutch performances should be taken into account. It may not be the best way to predict which goalie is going to perform the best in this year's playoffs, but in terms of their overall playoff contribution it would be unfair if it was not taken into account.

It is somewhat difficult to isolate what exactly is a "clutch" situation. Often these are defined to be situations like leading by a goal or the last five minutes of the game. These seem to be pretty arbitrary, since goals allowed in the first period count the same on the scoreboard as goals allowed in the third. Also, game dynamics often change in those situations, i.e. some teams alter their play to a more defensive style than others, which has a hidden impact on the results. In a way, in fact, a goalie's entire playoff performance could be considered to be taking place in a "clutch" situation.

One situation can pretty safely be considered clutch, however: sudden death overtime. When it comes down to next goal wins, the pressure on the goalies is at its greatest. Overtime play should therefore be a strong factor in evaluating clutch play.

To calculate overtime performance, I looked not only at record but also at estimated save percentage. This was found by finding out the rate of shots against during the entire game, and interpolating to find the estimated number of shots against during the overtime session alone.

OT Winning Percentage:
Roy .684, Belfour .525, Hasek .500, Cujo .481, Brodeur .296

OT Save %:
Belfour .944, Roy .942, Hasek .935, Cujo .926, Brodeur .902

Patrick Roy was the undisputed king of overtime hockey. Belfour edges him in save percentage, but Roy became a legend by winning in overtime, especially during the magical run of 1993. Belfour and Hasek were also very good. Martin Brodeur has been surprisingly poor in overtime. Amazingly, despite playing less than half as many OT games as Roy, Brodeur has actually lost more of them. This is a fairly sizable strike against Marty.

Goalies also face greater pressure in elimination games. The threat of the season ending should add extra meaning and pressure to the goalie's performance. It is difficult to isolate elimination games, but certainly game sevens are pressure-packed since they are elimination games for both teams. Game sevens also indicate that teams are playing at roughly the same level - a totally overmatched team is unlikely to make it to game seven. Therefore, game sevens are also considered in the analysis.

Game 7 Save %:
Hasek .946, Brodeur .928, Belfour .921, Roy .907, Cujo .900

Head-to-head record Game 7s:
Belfour .833, Hasek .667, Cujo .571, Brodeur .500, Roy .462

Hasek has only played three game sevens, and despite losing two of them has played well in all three. Brodeur and Belfour have good records in rubbermatches. Game sevens haven't been so kind to St. Patrick, who holds the record for the most career losses in game sevens. His save percentage hasn't been great either.

Combining the two, we get one concise "clutch save percentage" statistic, including performance in OT and game sevens.

Save percentage (game 7 and overtime):
Hasek .939, Belfour .936, Roy .924, Brodeur .915, Cujo .913

Hasek barely edges out Belfour for top spot. However, Belfour has played in more overtime games and game sevens. In particular, Hasek's game seven results are from a very small sample. Belfour's overtime record is a little better as well. That's enough for Eddie the Eagle to take top spot. Roy was the best in overtime, but his game seven record was weak. With era adjustments, however, his save percentage would be a little higher. That's enough to edge out the Dominator for second place. Brodeur and Cujo are pretty close overall, but Cujo gets the slight edge because of Brodeur's awful overtime record.

Overall Clutch Rankings:
1. Belfour
2. Roy
3. Hasek
4. Cujo
5. Brodeur

2 comments:

Anonymous said...

wow, after wasting a whole bunch of my time i was able to calculate martin brodeur's overtime save percentage. it comes out to .927 which is incredibly different from the one posted here. this site is nothing more then typical blogger garbage

The Contrarian Goaltender said...

Anonymous: The above numbers were based on interpolating shot totals, so they were estimates only. However, the Hockey Summary Project gives boxscores for nearly every OT game Brodeur has ever played. The complete results are as follows:

4/27/1994: 20 SA, 1 GA
5/03/1994: 5 SA, 1 GA
5/15/1994: 12 SA, 0 GA
5/19/1994: 11 SA, 1 GA
5/27/1994: 20 SA, 1 GA
5/12/1995: 6 SA, 0 GA
5/26/1995: 10 SA, 0 GA
6/07/1995: 3 SA, 1 GA
4/24/1997: missing data
5/11/1997: missing data
4/22/1998: 8 SA, 1 GA
4/26/1998: 2 SA, 1 GA
5/02/1999: 4 SA, 1 GA
6/08/2000: 19 SA, 1 GA
6/10/2000: 2 SA, 0 GA
4/18/2001: 1 SA, 1 GA
4/28/2001: 0 SA, 0 GA
5/01/2001: 3 SA, 0 GA
4/19/2002: 8 SA, 1 GA
4/24/2002: 5 SA, 1 GA
4/26/2003: 4 SA, 0 GA
5/02/2003: 22 SA, 0 GA
5/10/2003: 1 SA, 1 GA
5/21/2003: 7 SA, 1 GA
5/31/2003: 5 SA, 1 GA
6/02/2003: 2 SA, 1 GA
5/08/2006: 3 SA, 1 GA
4/18/2007: 5 SA, 0 GA
4/28/2007: 14 SA, 0 GA
4/13/2008: 1 SA, 0 GA

We can estimate the numbers for the two missing games because the game shot totals are on hockeygoalies.org. I estimate that on 4/24/1997 Brodeur was 18 SA, 1 GA, and on 5/11/1997 he was 6 SA, 1 GA.

Add all that up, and you get 227 shots against and 19 goals allowed, which works out to a .916 save percentage. How does that reconcile with my numbers above? Well, the original post was from 2007. Since then Brodeur has played in three OT games and has made 20 stops without allowing a goal. Comparing the time period covered in my original post, my estimated result was .902, and Brodeur's actual save percentage was .908. Not exact, but quite close.

Brodeur's OT results have improved a bit since the post, but he stills ranks behind Roy, Belfour, Hasek and Joseph in OT results for his career, so I'd probably still rank the goalies in the same order as before.