Puck Prospectus - Behind The Net

July 7, 2009
Behind The Net
Analyzing The Sharks' Defense

by Gabriel Desjardins

One of the downsides of writing about hockey statistics is not necessarily getting to watch all that much hockey. So I decided to watch video of every even-strength goal the San Jose Sharks gave up during the regular season this year. (Needless to say, I no longer feel like I haven’t watched enough hockey.) This was a very instructive experience with a hundred or so fifteen-second clips of defensemen and sometimes forwards not picking up their men, going to the wrong spot on the ice or just generally getting deked out of their shorts. For an example of this, watch this clip of Dan Boyle getting completely embarrassed – one of the worst goals the Sharks gave up all season at even-strength.

At any rate, over the course of watching all of the goal clips, I tried to figure out who was at fault on every single goal. This is not unlike David Staples’ “error” stat, but I think Staples probably pays closer attention to the game footage than I did, and he uses the actual game tape, so he can see a play develop further ahead of time than I do. This is one of the problems with subjective evaluation of hockey, but as you’ll see below, it gives us a lot more to evaluate than pure statistics.

In the table below, I’ve combined some traditional and advanced statistics for the Sharks defensemen along with the results of watching all of the game video:

NAME	  GP   TOI/60  GAON/60   GA   ERRORS   RATING/82   LR/82   QCR
VLASIC	  82   17:15   1.99	 47   11        57	    17	    1
BOYLE	  77   17:02   2.01	 44   21         1          -1	    4
EHRHOFF	  77   15:34   2.35	 47   20      -101          -5	    5
MURRAY	  75   14:32   1.87	 34    7       -15         -19	    6
BLAKE	  73   14:51   1.83	 33   14        91	    20	    2
LUKOWICH  58   14:18   1.88	 26   15       -19	    -2	    7
SEMENOV	  47   11:49   1.73	 16   12        26         -10	    3
STAUBITZ  35    6:05   0.84	  3    1        -9         -92	    9
JOSLIN	  12   10:34   2.84	  6    4      -379	    -2	    8

Just to explain the various statistics: Rating/82 is a player’s +/- relative to his teammates prorated to 82 games and 17 minutes of 5-on-5 TOI per game. Linemates Rating (LR) is the average Rating of the players each defenseman played with, while Qual Comp Rank (QCR) ranks players by the average Rating of the players they played against. A more in-depth explanation is available here.

So what does this exercise tell us?

Brad Staubitz and Derek Joslin are obviously minor leaguers at this point, and the Sharks have yet to trust them against real NHL competition.
Brad Lukowich and Alexei Semenov are complete disasters in the defensive zone. In my notes, I repeatedly wrote “Semenov giveaway direct to open goal scorer,” and “Lukowich falls down.” The Sharks realized this, using Semenov on the wing and not re-signing him at the end of the season. Lukowich is under contract for one more year, but might frequently find himself a healthy scratch next season.
Blake and Vlasic are the Sharks’ best defensemen, with Vlasic the clear #1. They faced opponents’ top lines, limited scoring, made few obvious mistakes and put goals on the board. They also had the good fortune to play with San Jose’s first-line forward unit.
Douglas Murray is probably the Sharks’ best defensive defenseman. He often went out with the third-line forwards and was reasonably effective at shutting down the other team’s second- and third-lines. He made the fewest obvious mistakes of anyone on the defensive crew.
Christian Ehrhoff gave up a lot of goals despite not matching up against opponents’ best players. He made a lot of mistakes and generated virtually no offense. He is not a top 4 defenseman and is significantly overpaid compared to Murray and Vlasic. Fortunately, he’s only signed for two more years.
Dan Boyle is a disaster defensively. This may be heresy to Sharks fans, who love watching his quick moves with the puck in the defensive zone, but he’s just a cut above the execrable Brian Campbell in his own zone. Boyle was at fault on almost half the goals that were scored against him while he was on the ice, with contributions ranging from not picking up his man to outright giveaways to getting beaten one-on-one. The net result was that Boyle’s linemates had the same +/- whether they played with him or not. This is not the hallmark of an elite defenseman.

So what did I learn from watching all that footage? Ultimately not that much, aside from reinforcing my perception of how good Douglas Murray is defensively and how bad Boyle and Ehrhoff are in their own zone. The Sharks coaching staff overplayed Ehrhoff a bit, but otherwise their icetime decisions made sense given the apparent performance of their players. The best outcome is that the observations you’d make by watching the games closely are the same as those you’d make by looking at the stats alone.

Gabriel Desjardins is a contributor to Puck Prospectus and runs the statistical hockey site BehindTheNet.ca