Let’s talk about ice time. Not goals. Not assists. Yes, ice time. During a game, it’s the key control a coach has over players. It can tell you a lot about trust, the system and the makeup of a team. It’s about pace for a long season and, in the case of the Boston Bruins, Stanley Cup aspirations. Ice time data is like DNA. It can reveal a lot about a coach and a team.
To get an idea of how Bruce Cassidy manages his bench relative to the other coaches, I collected the data of all players time on ice, and plotted the data on a Box Plot. Even without knowing anything about a Box Plot, we can let the visual graphic tell the story.
To gain more insight, we must first understand the Box Plot more intimately. The dark blue dots represent players (forwards only). The blue shaded box area represents 50% of ice time distribution. The middle of the box, denoted by the separation in the blue shade, represents the median. The top and bottom black lines (whiskers) represent normal 1.5x distribution of the box. Anything outside those ‘whiskers’ is considered outside the norm; or ‘outliers’. Yes, I had to watch a YouTube video to refresh my dusty knowledge on Box Plots.
I added orange reference lines to illustrate the highest ice time per game among Bruins forwards, Brad Marchand at 19.46, and the lowest, David Backes at 9.38 mins per game. It’s easy to see that the Bruins are not the most evenly distributed ice time team in the NHL; nor are they the widest. They also do not have any outliers; a player getting more than 1.5 of the core (the blue box) average.
There are 17 teams that stretch the ice time of one or more forwards farther than Marchand. And there are 10 teams that have a wider – top to bottom – distribution of ice time than the Bruins. The team with the tightest distribution of ice team is Bruin’s former coach Claude Julien’s Montreal Canadiens. For comparison sake, the top Canadiens forward is Phillip Danault with 17:74 time on ice per game (TOI/GP) and the lowest is newcomer Nick Cousins 12:60 TOI/GP.
This tells me that, even though the Bruins have one of the most prolific first lines in the NHL, Bruce Cassidy is managing his bench with a long view. He also has the luxury of good depth, which some teams do not, and it shows in their ice time distribution.
checked last seasons data. final four teams – only 2 teams had a forward who averaged more than 20 mins/gm (Aho and O'rielly). and barely over 20mins.
— Jason Paul ☘️ (@WaveIntel) October 29, 2019
It seems that teams are increasingly playing with more pace and paying more attention to fatigue to optimize health and momentum going into the playoffs. This season, there are 12 teams deploying one forward or more with 20-plus minutes per game. Last season, there were 17 teams doing the same. It will be interesting to see if this is a trend moving forward in player deployment.
As for the Bruins, it seems that Bruce Cassidy is being as consistent as last season when Marchand’s 19.62 mins per game was the top Bruins forward. It seemed to work last season when the Bruins went to the Stanley Cup Finals. The coach is driving his players for the long haul again this season.