(Mark Goldman/Icon Sportswire)

Earlier today, the Boston Bruins announced that defenseman Dennis Seidenberg will be sidelined for two months after undergoing back surgery. At first glance, this may seem like a big blow, as Seidenberg averaged the second highest ice time on the team last season. But, take a closer look and the Bruins could stand to improve their blue line’s performance from this injury.

Last season, Troey Krug was given far less minutes then he deserved, and Seidenberg far more. Seidenberg’s injury provides the Bruins with an opportunity to use Krug–the superior player–more frequently and appropriately.

As a general disclaimer, you can read these links about how zone starts and quality of competition are not enough to explain the disparity in performance between these two players.

Possession and Scoring Chances

When it comes to puck possession, Krug posted very strong numbers in 2014, while the Bruins generally got shelled with Seidenberg was on the ice. For better context, the chart below from War on Ice includes all five Bruins defenders who skated 800-plus 5v5 minutes last season. The x-axis is the percentage of the team’s 5v5 minutes that a player skated. The y-axis is how the team fared in shot attempts with the player on the ice.

Seidenberg was the Bruins most used defender last season, skating, 38.1 percent of the Bruins 5v5 minutes. Krug, on the other hand, was used the least of the five defenders displayed, having played 31.85 percent of 5v5 minutes.

The y-axis shows that, if the Bruins care about possessing the puck, deploying Krug and Seidenberg in this way is a mistake. The Bruins fared 2.47 percent better in shot attempts when Krug was on the ice as opposed to on the bench and 5.68 percent worse while Seidenberg was skating.

When looking at War on Ice’s definition of scoring chances, the disparity is even greater, as the Bruins had 2.08 percent more of the scoring chances when Krug was playing and 7.06 percent less while Seidenberg was.

Production and Goals

In the chart below (also from War on Ice) the x-axis represents the player’s points per 60 minutes of ice time and the y-axis is the player’s relative goal differential (the percentage of total goals that were scored by the Bruins when the player was on the ice as opposed to when he was off).

The higher and further right a player is, the better. The lower and further left, the worse.





Krug was the only Bruins defender who improved the team’s percentage of overall goals while he was on the ice, and he did it by a wide margin at 12.11 percent. Is his 102.25 PDO due to regress? Sure, the underlying numbers suggests he’s still a very effective player who the Bruins under utilize. The Bruins had 6.96 percent less of the goals when Seidenberg was on the ice as opposed to when he was on the bench.

Krug’s 0.94 points per 60 ranked second among the Bruins defenders in the sample and 44th league-wide among the 167 defenders who skated 800-plus 5v5 minutes in 2014-15. Seidenberg, at 0.51, finished third and 135th, respectively.

Protecting the Lead

Earlier in the week I looked at defensemen who are trusted too much by their respective coaches to protect a lead.

A couple reminders from the previous post: First, the sample is from 2012-15, all defensemen who have skated at least 600 minutes of 5v5 hockey while their team was leading. Second, the labels are overly simplistic, but just meant to give a general idea of where players fall.

There are 155 defensemen in the sample, and the difference in usage and results between Krug and Seidenberg could hardly be more drastic.

Krug’s TOI% was 151st while his relative possession numbers were 8th. Seidenberg, on the other hand, ranked 8th in TOI% and 150th in relative puck possession. So, Krug was one of the most effective defenders in the sample, but one of the least used, while Seidenberg was one of the least effective but one of the most used.

It isn’t often that a team could improve itself from losing one of it’s workhorses on the blue line. But, given the way the Bruins erroneously deployed Krug and Seidenberg last season, this could be the case. While no injury is to be celebrated, and here’s to a quick recovery for Seidenberg, the Bruins now have a bigger opportunity to use Krug as often as they should and, in doing so, reap the benefits. Will they do it?