So yesterday I ran down the numbers on a new statistic that's targeted at determining who the best defensive defensemen are in the NHL. I referred to it as the SDI or Shut Down Index, and to briefly summarize it compares a blue liner's Corsi REL QoC, Corsi REL QoT, OZ%, Corsi ON/60, and Penalty Differential to their peers in a given season using the number of standard deviations above or below average in each category (with a 20% weighting on Penalty Differential).

I was pretty happy with the results but there were a few inquisitive minds that seemed to misunderstand the point of the exercise. I am NOT looking to determine who the best all-around defender is in the NHL with this statistic. I am well aware that many top D men will not fare well in these rankings as a result of their higher OZ% and Corsi REL QoT. What I was trying to determine, and this is the key part, is who is doing the best job while carrying a heavy defensive work-load in the NHL.

Today I plan on carrying the work forward a little bit further - in an effort to assess who the best Shut Down D are in the NHL right now, and secondly giving you all a glimpse of how the Toronto Maple Leafs have fared since 2007-08 in this regard.

Season over season there seems to be a fairly high level of variation for some defensemen, and there also seemed to be some pairing effects - likely stemming from how regularly D men play with their partners at even strength. While I think this is important to note, I also think it's interesting to see what happens to players that carry on a high level of impact after switching teams or playing with new partners. With this in mind I give you the following list of the top 25 NHL D men by SDI over the past 4 years that are still playing in the NHL.

*Note that there was a minimum of 3 seasons worth of data for inclusion on the list*

RK Player GP SDI
1 Jan Hejda 269 3.074
2 Barret Jackman 255 2.693
3 Roman Polak 250 2.510
4 Dan Hamhuis 273 2.472
5 Zdeno Chara 286 2.216
6 Marc-Edouard Vlasic 271 2.157
7 Jay Bouwmeester 296 2.143
8 Anton Volchenkov 230 2.060
9 Karl Alzner 160 2.057
10 Chris Phillips 246 2.043
11 Eric Brewer 182 1.998
12 Duncan Keith 288 1.982
13 Victor Hedman 184 1.903
14 Brent Seabrook 288 1.826
15 Stephane Robidas 274 1.757
16 Willie Mitchell 230 1.720
17 Marc Methot 243 1.681
18 Drew Doughty 283 1.635
19 Henrik Tallinder 269 1.629
20 Keith Ballard 272 1.614
21 Tim Gleason 264 1.557
22 Marc Staal 241 1.550
23 Paul Martin 192 1.531
24 Niklas Kronwall 254 1.489
25 Kevin Klein 267 1.431

Honourable mentions go to Radek Martinek (2.400), PK Subban (2.357), John Carlson (2.220), Mike Lundin (2.159), and Aaron Rome (1.437), who all missed the list due to a lack of enough seasons or games played due to injury, but would have ranked in this group otherwise.

Also worth noting at this point is the caveat regarding pair effects. Dan Girardi of the New York Rangers would rank 30th by this measure over the past four years, with a SDI average of 1.314, which looks stellar. Unfortunately this could possibly be explained by the high level of play of his defensive partners over the past few seasons.

In 2007-08 and 2008-09 when Girardi was playing much easier minutes, his SDI scores were 0.938 and -0.270 largely due to his SDI Sit scores of -0.338 and -1.258. Over the next three seasons his SDI has risen dramatically to +1.065, +2.257, and +2.581. While this indicates some improvement over time in his play, in the two seasons prior to this his defensive Partner was Marc Staal (number 22 on the aforementioned list), who posted SDI scores of +1.128, +2.867, and +3.076 for the 08-09, 09-10, and 10-11 seasons respectively. Far and away better numbers than Girardi.

This season Staal has missed time due to a concussion, but in his place has been another blue chip defensive prospect in Ryan McDonagh, who so far this season has posted an SDI score of +2.815, again well above Girardi's score. So just to summarize this point - Girardi's SDI score has been below that of his primary defensive partner for the past three years by an average of 0.951 points. His numbers are getting closer to theirs, but he's still the 2nd best in his pairing in all of those years. This point is important when considering the value of players such as oh... I don't know... Ryan Suter (average of +0.339) and his pairing with (the younger) Shea Weber (average of +1.183). Keep that in mind Unicorn Hunters.

The last portion of this analysis I wanted to explore is the seasons of Toronto Maple Leafs Defensemen in recent memory, and luckily since we have data dating back to 2007-08 we can do that fairly easily. Here are the Leafs D men over the 2007-2012 span, and their average SDI scores for seasons where they played over 30 games.

*Note for players traded mid-season, the entirety of the given season's data is used due to limitations in the btn data - the GP number is Leafs games only*

Player Seasons GP SDI Sit Avg SDI Res Avg SDI Avg
Garnet Exelby 2009-10 51 1.453 0.168 1.620
Dion Phaneuf 2010-12 141 0.866 0.309 1.174
Ian White 2007-10 208 -0.194 1.215 1.021
Francois Beauchemin 2009-11 136 0.453 0.478 0.931
Carl Gunnarsson 2009-12 159 0.889 -0.196 0.693
Jonas Frogren 2008-09 41 0.735 -0.746 -0.011
Tomas Kaberle 2007-11 279 -1.127 0.850 -0.271
John-Michael Liles 2011-12 34 -0.257 -0.049 -0.306
Luke Schenn 2008-12 279 -0.055 -0.381 -0.436
Bryan McCabe 2007-08 54 -0.414 -0.048 -0.462
Jake Gardiner 2011-12 42 -0.831 0.280 -0.551
Mike Komisarek 2009-12 135 -0.192 -0.458 -0.650
Jeff Finger 2008-10 105 -0.319 -0.651 -0.970
Keith Aulie 2010-11 40 1.830 -2.873 -1.044
Cody Franson 2011-12 34 -1.652 0.604 -1.048
Pavel Kubina 2007-09 154 -1.089 0.002 -1.086
Brett Lebda 2010-11 41 -0.969 -0.126 -1.095
Anton Stralman 2007-09 88 -1.784 0.654 -1.130
Andy Wozniewski 2007-08 48 -0.583 -0.942 -1.524

So I said there were reasons for optimism in Leaf Land when I first presented this statistic yesterday, and frankly looking at the above list I could understand having the opposite feeling. The sad fact that the closest thing the Leafs have had to a shut down defender in the past 5 years is Garnet Exelby is extremely scary. It also explains why we had to give up Ian White and Francois Beauchemin to get players like Dion Phaneuf, Jake Gardiner, and Joffrey Lupul in exchange... they were our top pieces on the blue line.

It also seems fortuitous that we managed to exchange Brett Lebda for a younger Cody Franson (who is an offensive piece not defensive) and Matt Lombardi who helps our forward depth. We also lucked out in moving Tomas Kaberle for futures like Joe Colborne and draft picks when we did, so that trade was extremely well timed.

Realistically what this list shows is that only 6 Leafs blue liners in the past five seasons have been asked to regularly match up versus top opposition primarily in the defensive zone: Exelby, Phaneuf, Beauchemin, Gunnarsson, Frogren, and Aulie. These are basically the only guys the coaches have deemed reliable enough defensively to play in these situations. Luckily 3 of them are currently on the team, unfortunately only 2 of the 3 have played the role succesfully. Keith Aulie has been pretty horribly outmatched so far in his NHL career, and his lack of puck handling skills largely prevent him from being much use in a game focused on maintaining control of the puck.

Dion Phaneuf (0.301) doesn't appear to be in the defensive elite of the NHL over the past 5 years, but his numbers are superior to the likes of Matt Carle (0.257), Scott Hannan (0.235), Kevin Bieksa (0.181), Trevor Daley (0.167), James Wisniewski (0.167), Mattias Ohlund (0.146), Roman Hamrlik (0.126), Dennis Seidenberg (0.110), and Michal Roszival (0.086).

Carl Gunnarsson has been even more impressive in his early career (0.693). His peers over the past few years may be even more surprising. One of his closest comparables in SDI Avg since 2007-08 is Chris Pronger (0.702). He is also ahead of Bryce Salvador (0.656), Alex Goligoski (0.625), Tyler Myers (0.542), Ian White (0.523), Zach Bogosian (0.471), Brett Clark (0.376) and that unicorn people seek - Ryan Suter (0.339).

I hate to say it but this assessment leads me further to the conclusion that it may be a decent time to cut bait on Luke Schenn. He has struggled to play any sort of puck control game, and he may be out of his depth as a shut down style player. Hopefully he turns his game around in the last 30 games of this season and going forwards in his Leafs career.

Please note this is purely an assessment of how a defender deals with defensive assignments, NOT a determination of offensive success. I hope this pre-empts any hate mail that comes my way. Again, any further suggestions or comments are welcome.

In light of Ryan Suter's results compared to Shea Weber's, do you still think the Leafs should be pursuing him this off season?

They need to sign him no matter the cost.8
At the right price he's still worth signing.36
We won't get him anyway - what about Bryan Allen (0.918)?40