Hockey 201: Zone Start and a Coach’s Trust

When watching a hockey game on TV or even in the arena itself, fans will never notice the chess match going on behind the benches. Coaches constantly try to match up their lines against their opponents’. The home team gets the advantage of sending out their lines last. So, no matter who his rival chooses, the home coach gets to respond. A zone start is the advanced statistic that tracks where a player begins his shift at the faceoff.

The Zone Start and Math

Simply put, a zone start is tracked by counting which zone a player starts his shift in when his shift begins with a faceoff. The three zones are offense, neutral, and defense. The stats are ZSO (Zone Start Offense), ZSN (neutral), ZSD (defense). But the raw numbers are not worth much without a comparison. That’s where ZSO% comes in. This percentage compares the number of offensive starts to the number of defense and offense starts.

Evgeni Malkin
(Kevin Hoffman-US PRESSWIRE)

For example, let’s take a look at Devils defenseman, Adam Larsson. In the 2015-16 regular season, Larsson started 308 shifts in the offensive zone, 520 neutral zone, and 660 defensive zone. His ZSO% is 308/(308 + 660) which comes to 31.8%, the lowest percentage in the league among defensemen. Note that the neutral zone starts are pretty much ignored. This is because of the overarching reason behind zone start stats. Which players are tasked with defending their net on a faceoff most often?

Winning Your Coach’s Trust

A defensive zone start is important to track. More of those could imply two things: your team is spending a lot of time hemmed in their own end and/or your coach trusts you to keep opponents out of your net.

As the law of averages tends to even things out, ZSO% says more about a player’s specialties. Extremely high percentages imply a player is more offensively minded and trusted to score. While low percentages, like the above Larsson’s, imply he is tasked most often with defending his net when his goalie is in the most danger. With his back nearly touching his own netminder, it shows that his coach trusts him in the toughest moments of the game.

(Amy Irvin / The Hockey Writers)
(Amy Irvin / The Hockey Writers)

In contrast, rookie scoring sensation, Shayne Gostisbehere, had a ZSO% of 60.91. Due to his knack for finding the net, his coach likely trusted him to attack the net more often.

Relative and Off the Ice

Just like Corsi, the zone start stat tracks relative and off ice stats. These compare the zone starts of a single player to the collective starts of the rest of the players while he is off the ice. What this will tell you is how his presence impacts the game. A negative relative ZSO% means that this player is in his own zone more often than his teammates.