Using Data-generated Scouting to Quantify Defensive-play

By Kicks @Chrisboucher73
Defensive-play remains one of the most difficult aspects of a player's performance to quantify. That said, data-generated scouting provides exclusive data that can be used to break down and compare each player's performance in a specific zone, or in a specific situation. It's important to note that defensive-play can be quantified in all zones, but for the purpose of this post, I will focus on the defensive-zone.
DEFENSIVE-ZONE RATIO
Answering the question, how well does a player perform in the defensive zone?
Defensive-zone ratio expresses the number of successful plays in the defensive-zone each player produces for every 1 failed play. 
Defensive-zone events used in this calculation include; stick-checks, body-checks, loose-puck recoveries, loose-puck recoveries off of rebounds, loose-puck recoveries off of faceoffs, d-to-d passes, stretch passes, outlet passes, dekes, dekes along the wall, dump-outs, dump-outs that are rimmed around the boards, blocked shots, blocked passes, and missed passes (when receiving a pass from a teammate).
As a team, the Habs defensive-zone ratio improved in regular season games that occurred after the Olympics, and remained comparable during the playoffs.
Among defensemen, the defensive-zone ratio dropped immediately following the Olympics, but rose again during the playoffs. The top ratio among defensemen prior to the Olympics was produced by PK Subban, while the top ratio after the Olympics and during the playoffs belonged to Josh Gorges.
The lowest d-zone ratio among d-men both prior to, and immediately following the Olympics belonged to Jarred Tinordi (small sample size). Among d-men with larger sample sizes, Douglas Murray had the lowest ratio. The lowest ratios during the playoffs belonged to Nathan Beaulieu and Douglas Murray. That said, among d-men with substantial playoff ice-time, the lowest d-zone ratio at even-strength belonged to Mike Weaver.
Among centres, The defensive-zone ratio rose immediately following the Olympics, but dropped during the playoffs. The top defensive-zone ratio prior to the Olympics was produced by Lars Eller, while Tomas Plekanec had the top d-zone ratio after the Olympics. The top defensive-zone ratio during the playoffs was contributed by Desharnais.
The lowest defensive-zone ratio prior to the Olympics was produced by Daniel Briere; although Briere also played on the wing. Among players who played center exclusively, the lowest pre-Olympic ratio belonged to Desharnais. The lowest during regular season games following the Olympics was produced by Eller, while Plekanec had the lowest defensive-zone ratio among centres during the playoffs.
Among wingers, the defensive-zone ratio rose substantially following the Olympics and into the playoffs. The top defensive-zone ratio prior to the Olympics was produced by Brian Gionta. the top ratio after the games belonged to Brendan Gallagher; as Brandon Prusts sample size over this period was small. The top defensive-zone ratio among wingers during the playoffs was also produced by Gallagher; whose defensive-game produced substantially-better results than his teammates immediately following the Olympic break.

DEFENSIVE-ZONE EVENTS PER-60
 Answering the question, how involved is a player in the defensive-zone?
This graph reflects the number of even-strength events in the defensive-zone each player averaged per-60 minutes. This helps us determine which players are most involved in the play while the puck is in the defensive-zone.
Defensive-zone events used in this calculation include; stick-checks, body-checks, loose-puck recoveries, loose-puck recoveries off of rebounds, loose-puck recoveries off of faceoffs, d-to-d passes, stretch passes, outlet passes, dekes, dekes along the wall, dump-outs, dump-outs that are rimmed around the boards, blocked shots, blocked passes, and missed passes (when receiving a pass from a teammate).
The average Canadiens player averaged just over 100 even-strength defensive-zone events per-60 both during the season, as well as in the playoffs.
Among defensemen,  Nathan Beaulieu averaged the most defensive-zone events per-60 both before and after the Olympics. That said, his sample size was substantially smaller than other Montreal d-men. Among those defensemen, PK Subban averaged more defensive-zone events per-60 both before and after the games. During the playoffs, Mike Weaver averaged more defensive-zone events per-60 than any other d-man with substantial playoff ice-time.
Habs centremen were more involved in the defensive-zone during the playoffs than they were during the regular season. Lars Eller averaged more defensive-zone events per-60 than any other Montreal center both before and after the Olympics, as well as during the playoffs.
Among players who played exclusively as centremen, David Desharnais averaged the fewest d-zone events per-60 both before and after the games, as well as in the playoffs.
Among wingers, Brandon Prust averaged the most defensive-zone events per-60 before the Olympics, while Michael Bournival averaged the most after the games. Outside of Travis Moen's small playoffs sample size, Bournival also averaged the most defensive-zone events per-60 among wingers during the playoffs.

PERCENTAGE OF DEFENSIVE-ZONE EVENTS SPENT DEFENDING IN D-ZONE
Answering the question, how much of the player's "time" spent in the defensive-zone is spent defending? 
This graph reflects the percentage of events engaged in while in the defensive-zone that can be classified as defensive. Defensive-events include all events engaged-in while attempting to remove puck-possession from the opposition. Defensive-plays used in this calculation include stick-checks, body-checks, blocked shots, and blocked passes.
This calculation allows us to look deeper into the results communicated in the above graph. While defensive-zone events per-60 tell us who is the most involved players in the defensive-zone, this graph separates the results in order to determine which players have possession during those d-zone events, and which players are using the bulk of those events to remove possession from the opposition.
Logically, players who use up a high percentage of their defensive-zone events attempting to remove possession have less opportunity to move the puck out of the defensive-zone, while also allowing the opposition more opportunities to create scoring-chances.
As a team, Montreal engaged in a lower percentage of defensive-zone events while defending immediately following the Olympics, but that percentage rose during the playoffs.
Among defensemen, Douglas Murray engaged in a higher percentage of defensive-events without possession than any other Montreal d-man; both before and after the Olympics, as well as during his limited playoff action. This does an excellent job of expressing the direct result of a high defensive-zone turnover-rate as quantified in the graph further down showing defensive-zone puck-possession success-rates.
At the opposite end of the spectrum we see PK Subban. Subban engages in the lowest percentage of his defensive-zone events without possession. Expressed differently, this tells us that Subban has possession far more often when involved in the defensive-zone than any other Montreal d-man. As a result, Subban offers the opposition fewer opportunities to create offense.
Among forwards, Desharnais engaged in a higher percentage of defensive-zone events without possession in games that occurred before the Olympic break. The highest percentage of d-zone events without possession following the games was contributed by Michael Bournival; who also contributed the highest percentage during the playoffs.
The lowest percentage of defensive-zone events without possession before the Olympics was produced by Brandon Prust, while the lowest percentage after the Games belonged to Thomas Vanek. Brian Gionta and Dale Weise engaged in the lowest percentage of defensive-zone events without possession during the playoffs.

PERCENTAGE OF TOTAL EVEN-STRENGTH EVENTS SPENT DEFENDING IN D-ZONE
 Answering the question, how much "time" spent on the ice is spent defending in the defensive-zone?
This graph reflects the percentage of all events engaged in that occur while defending in the defensive-zone. Unlike the above graph, this calculation divides the number of defensive-events in the defensive-zone by all events in all zones.
It can be used to help differentiate between offensive and defensive-players; particularly among defensemen.

DEFENSIVE-ZONE PUCK-POSSESSION SUCCESS-RATE
Answering the question, how successful is a player at moving the puck out of the defensive-zone without turning it over?
These percentages represent each player's success-rate when attempting a play with possession of the puck in the defensive-zone. Plays used in this calculation include; passes, dekes, and dump-outs. Sub-categories for passes include; d-to-d passes, stretch-passes, and outlet passes. Sub-categories for dump outs include; open-ice dump-outs, dump-outs off of the wall, and rim dump-outs. Sub-categories for dekes include dekes along the wall, and open-ice dekes.
Each puck-possession play included above is scored as either successful or failed; depending on the result.  Success-rates are simply calculated by dividing the number of successful puck-possession plays by the number of total puck-possession plays attempted.
Another way to look at the results is to subtract the puck-possession success-rates from 100. This number will give us each player's turnover or giveaway-rate.
As a team, the Habs defensive-zone puck-possession success-rate improved following the Olympics, and held that level throughout the playoffs.
Among defensemen, PK Subban produced the top defensive-zone puck-possession success-rate prior to the Olympics, while Gorges had the top success-rate after the games. Expressed differently, this shows us that both Subban and Gorges also had the lowest defensive-zone turnover-rates during the periods mentioned.  Gorges had the top d-zone possession success-rate during the playoffs; with Subban posting the second-best success-rate.
Among defensemen with substantial even-strength ice-time, Douglas Murray produced the lowest defensive-zone puck-possession success-rate in games that occurred both before and after the Olympics. He also had the lowest possession success-rate in the playoffs. But, in his defense, he had a smaller sample size than other d-men. Among those d-men with substantial playoff ice-time, Nathan Beaulieu had the lowest defensive-zone possession success-rate. Expressed differently, this tells us that (over each particular period) Murray and Beaulieu turned the puck over in the d-zone at a higher-rate than other Habs d-men.
Among forwards,  Lars Eller produced the highest defensive-zone puck-possession success-rate during games that occurred prior to the Olympics, while Plekanec had the top success-rate following the Games. Again, Prust's post-Olympic regular season sample size is too small to include his results. The top d-zone possession success-rate during the playoffs was produced by Gallagher; followed closely by Desharnais.
Daniel Briere posted the lowest defensive-zone puck-possession success-rate prior to the Olympics, while Bournival had the lowest success-rate after the games. The lowest defensive-zone puck-possession success-rate during the playoffs also belonged to Briere; followed closely by Vanek and Alex Galchenyuk.

DEFENSIVE-ZONE TAKEAWAY TO TURNOVER RATIO
Answering the question, how many defensive-zone takeaways does each player produce for every 1 turnover they commit?
For the purpose of this calculation, takeaways are defined as any successful play made when attempting to remove puck-possession from the opposition, while turnovers are described as any failed play while attempting to make a play with possession.
As a team, Montreal produced a better defensive-zone T-to-T ratio in the playoffs than they did at any point during the season.
This graph does an excellent job of quantifying the impact of Gorges in the defensive-zone. Gorges produced the top defensive-zone takeaway to turnover ratio among defensemen prior to the Olynpics, after the Olympics, as well as during the playoffs.
Among defensemen with substantial ice-time, Bouillon produced the lowest d-zone T-to-T ratio prior to the Olympics, while Weaver had the lowest ratio after the games. The lowest ratio among d-men during the playoffs belonged to Beaulieu, while Subban had the lowest T-to-T ratio among d-men with substantial ice-time. It's important to see the big picture when examining these results, as players with more possession events than defensive-events traditionally produce lower ratios.
Among players who played exclusively at centre, David Desharnais had far-and-away the best defensive-zone takeaway to turnover ratio both before and after the Olympics, as well as during the playoffs. Ryan White had the lowest d-zone T-to-T ratio prior to the Olympics, while Eller produced the lowest after the games. Briere had the lowest ratio during the playoffs.
Among wingers, Michael Bournival had the top defensive-zone takeaway-to-turnover ratio prior to Sochi, while Gallagher had the top ratio both after the Olympics, and during the playoffs.

SUCCESS-RATE IN THE DEFENSIVE-ZONE WHEN ATTEMPTING TO REMOVE POSSESSION FROM THE OPPOSITION
Answering the question, how successful is a player when attempting to remove puck-possession from the opposition in the defensive-zone?
This graph represents how successful each player is when attempting to remove puck-possession from the opposition while in the defensive-zone. It divides the number of successful attempts at removing puck-possession from the opposition by the total number of attempts; only defensive-zone events were used. Defensive-plays used in this calculation include stick-checks, body-checks, blocked shots, and blocked passes.
As a team, Montreal posted their top defensive-zone defensive success-rate during games that occurred prior to the Olympics.
Among defensemen, Francis Bouillon (followed closely by Gorges) produced the top defensive success-rate in the d-zone during games prior to the Olympics, while also posting the top success-rate after the games (followed closely by Subban). Among players with substantial playoff ice-time, Markov and his strong stick had the top success-rate when attempting to remove possession from the opposition in the defensive-zone; followed closely by Alexei Emelin.
The top defensive success-rate in the d-zone among forwards prior to the Olympics was produced by Brandon Prust, while the top success-rate following the game belonged to Gallagher (Prust's sample size).  Gallagher also posted a substantially better defensive-zone defensive success-rate than any other Montreal forward during the playoffs.

SCORING-CHANCES AGAINST PER-60

Answering the question, how many scoring-chances is each player directly responsible for giving up per-60 minutes of even-strength ice-time?
This graph communicates the number of even-strength scoring-chances AGAINST each player is directly responsible per-60 minutes. The higher the number, the more scoring-chances against this player is directly responsible for.
As a team, Montreal allowed more even-strength scoring-chances against per-60 during the playoffs than they did at any other point in the year. This playoff result is the product of the Boston and New York series, as the Habs averaged just 13.5 ES scoring-chances against per-60 versus Tampa Bay.
Granted his sample size is smaller than other d-men, but Jarred Tinordi simply was responsible for far too many scoring-chances against during the games he played. Among d-men with substantial ice-time, Murray was directly responsible for more ES scoring-chances against per-60 than any other Montreal d-man before the Olympics, while Emelin was responsible for more after the games. With a small sample size, Beaulieu was directly responsible for more scoring-chances against per-60 during the playoffs, while Weaver was responsible for the most among d-men with significant ice-time.

Only data-generated scouting can provide this level of detail or analysis. Feel free to email me with any question or comments about the work I do, or the services I provide.