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Blackhawks defenseman Duncan Keith
In an age where sabermetrics have taken the baseball world by storm, hockey has been slowly but surely heading down the same path. Websites like Time on Ice and Behind the Net have been accumulating data for years now, and a look at the information they can provide gives us an interesting glimpse into what is making the Chicago Blackhawks tick.
For instance, there have been some (author’s note: this includes me) who have questioned the play of guys like Duncan Keith in the playoffs. The eye test can sometimes give the correct impression of how a player is doing, but there are often things going underneath the surface that can prove otherwise. Keith is a sterling example of that, because he and former defense partner Brent Seabrook seem to be under scrutiny a good amount of the time.
Now, a look at their plus-minus would tell us that Keith has been the better player, with a +2 in comparison to Seabrook’s -1. Advanced statistics, however, will tell us that the disparity between the two has been even bigger (statistics compiled by BehindtheNet.ca):
|Player||Corsi Rel.||PDO||Off. Zone||Off. Finish|
Keith’s numbers this postseason in these categories have, in a word, been very good. Relative Corsi measures the ratio of how many shots for and against your team are taken over the course of 60 minutes. A positive number means that you take more shots, and a negative number means you allow more shots. This number massively favors Keith, but what’s even more interesting is that Keith and his teammates are getting more offensive opportunities, and he’s taking significantly fewer possessions that start in the offensive zone than Seabrook is, which is where the Offensive Zone % metric comes in.
The second number in that spreadsheet is the PDO number. This number basically measures how often your team possesses the puck when you are on the ice. As a team, the Blackhawks are extremely good in this category, because that is the strategy that head coach Joel Quenneville likes to employ. 1000 is the baseline for this statistic, so a player above it does a good job of possessing the puck, while a player below it gives up the puck to the other team more often than not. As the chart above shows, Keith is doing a much better job in that department than Seabrook, despite starting a larger number of possessions in the defensive zone.
Finally, the last two numbers provide one last comparison between the two players. Keith and his linemate Niklas Hjalmarsson have both started in the offensive zone about a third of the time in this series, as the spreadsheet shows, but they finish in the offensive zone nearly half of the times that they are on the ice. This 8% improvement is a solid number, and shows that the pairing is able to get the puck from the opposition and move it up the ice, and Keith has benefitted from this to the tune of a goal and two assists in three games.
As for Seabrook, he has not been able to get any benefit from starting in the offensive zone two-thirds of the time. He has zero points so far in the series, and only has four shots on goal in three games.
The conclusion we can reach from dissecting these statistics is a simple one: the eye test doesn’t always work. Duncan Keith may appear that he isn’t playing well, but based on these numbers, he is actually doing a very good job in preventing the Minnesota Wild from scoring, and he is helping to create scoring chances from his team despite his defensive workload. That is the hallmark of a good two-way defenseman, and Keith has a well-deserved reputation as one of those. If he and Hjalmarsson can continue to play these kind of shutdown minutes, the Hawks have an opportunity to go far, and also to prove a lot of doubters wrong.