I’ve alluded to the concept of open play Corsi% over the course of the summer, although I’ve never precisely quantified it, which is something that I should do. One of the confounding factors with Corsi% is the fact that players take faceoffs at different spots on the ice and some players take more faceoffs in the offensive zone; other players take more faceoffs in the defensive zone. One of the questions that people like me wonder about is how this affects things.
Over the summer, I came up with an answer to this question. The way I did it was pretty straightforward. I asked myself this question: “For how long after a faceoff is won or lost is there an impact on play?” There are two types of impact to worry about: the likelihood of the team winning or losing the draw getting or allowing shot attempts and the impact on the volume of shot attempts.
Hockey allows for tracking six types of faceoff: OZ wins, OZ losses, NZ wins, NZ losses, DZ wins and DZ losses. What I did was look at the 5v5 shot attempts 1 second after the draw, 2 seconds after the draw, etc. for the years 2007-13. Simple enough. We’ll start with offensive zone faceoffs.
What you’re seeing here are line graphs of the Corsi% of a team winning/losing an offensive zone faceoff n seconds after the puck was dropped. So, for example, teams winning an offensive zone faceoff have had a Corsi% of 69.8% in the thirteenth second post-faceoff win over the past six seasons. That drifts down and it isn’t until the 38th second post-faceoff win that they have a Corsi% that’s below 50%. It’s fun to be on the ice when you win an offensive zone faceoff.
Teams losing offensive zone faceoffs actually have the better of the Corsi% fight for the next ten seconds. When you think about it, this is obvious: if you lose an offensive zone faceoff, the other team still has to get the puck down into your end to generate a shot attempt, an activity that is fraught with risk and peril. From the 11 second mark through to the 18 second mark, they’re then below 50% in terms of Corsi%.
It’s not just the overall Corsi% that matters here – it’s also the total volume of shot attempts. If the Corsi% gets to 50% quickly, but the shot attempt volume is suppressed, then there’s still a faceoff effect. Let’s look at the shot attempt volumes, both for and against, for each faceoff type. Keep in mind – an OZ+ for one team is another team’s DZ-.
I’ve presented this on a per 100 faceoff basis. We see about what we’d expect. There’s a huge shot volume when a team wins an offensive zone faceoff – the team has possession and are close to the opposition net. It takes until the 23rd second following a OZ-/DZ+ situation until the shot volume equalizes though. Even though the team losing the draw gets to 50% Corsi-wise pretty quickly, there’s still an effect because of the reduced shot volume. I’ve been using 21 seconds as my cutline as far as that effect, along with 37 seconds post-OZ faceoff win.
For neutral zone faceoffs, there’s an effect that lasts for 29 seconds – in the 30th second, the team losing the faceoff is more likely to generate a shot attempt than the team that won it. We know from the graph above that the shot volume impact is gone before that so it’s pretty easy to see that there’s a neutral zone effect that lasts for 29 seconds.
The mathematically astute amongst you will recognize that the chart for defensive zone faceoffs looks a lot like the chart for offensive zone faceoffs. This is because, of course, one man’s DZ win is another’s OZ loss. So the same logic set out above applies and a defensive zone faceoff win sees an impact for ~21 seconds and a defensive zone faceoff loss results in a 37 second disadvantage.
If you want to talk about open play hockey then, when there are no faceoff effects present, the easiest thing in the world to do is just to knock out the shot attempts within x seconds of a certain type of faceoff. This will, I hope, put an end to the debate about how long the faceoff effect lasts for – this is the empirical answer, I think. The Corsi% in each of these situations is pretty damn consistent, year after year.
(The title is screwed up this graph – it should be “Post OZ Faceoff Loss.”)
Is this useful information? I think it is. I was struck by this comment about Colton Orr earlier this summer:
I think Orr has proven he’s more than just an enforcer. He was used a little on the third line this season, he is one of the more reliable guys at chipping pucks out, knowing the conditions of the game, chipping pucks out and chipping pucks in, changing smartly, and he’s very responsible on the back check.
This came from a man who is paid money to coach a professional hockey team. A proposition: if Colton Orr is “one of the more reliable guys at chipping pucks out” it will show up in his numbers following defensive zone faceoffs and they won’t be horrible. Reality: the Leafs had a 10.7% Corsi% in the 37 seconds following DZ faceoff losses last year with Colton Orr on the ice. Whether he’s good at chipping pucks out or not, teams are crucifying the Leafs in a situation in which a player’s defensive ability would appear.
Orr was on the ice for 12% of the Maple Leafs defensive zone faceoff losses at 5v5 in 2013. Amongst guys who were on for at least 10% of their team’s DZ losses, Orr’s 10.7% Corsi% ranks 3,428th out of 3,447 people with enough TOI to qualify. The Leafs were a garbage fire of historic proportions when they lost a DZ draw with Orr on the ice. That said, Orr actually surpassed the figures posted by a couple of other heavies last year: Chris Thorburn, Ryan Reaves and BJ Crombeen all posted even worse figures.
As far as Cronin goes, you wonder. Is he insane? Is he lying? Is he aware of how poor the Leafs results were in a defensive situation like this with Orr out there? I have no idea. We’re starting be able to measure stuff finely enough that we can ask these questions though. It’s hard to imagine any sort of a defence for the guy as a hockey player, no matter what the Leafs might say.Email Tyler Dellow at firstname.lastname@example.org