clock menu more-arrow no yes

Filed under:

What we’re talking about when we talk about defencemen shooting

New, comments

A short case study in the value of defender shooting.

Toronto Maple Leafs v Arizona Coyotes Photo by Norm Hall/NHLI via Getty Images

The issue of point shots and the amount defencemen shoot has been coming up a lot as the Maple Leafs put up a lot of shots this season, with a high pace of offence, but produced very low quality.

(Shots in the post refers to Corsi unless otherwise indicated.)

By Corsi For %, the Leafs are fourth in the NHL right now with 53% (all numbers from Natural Stat Trick), and have been in the top few teams all season. They’ve had no difficulty drving play on average. Their troubles have also not been offensive pace, where they are currently second in the NHL with 63 Corsi For, which is the same ranking they held last season with a very small drop in the rate itself.

The trouble for the Leafs has come in two stages. First the drop to Fenwick % (all unblocked shots) where they are 11th in the NHL, and then the drop in Expected Goals % where they are 22nd with 49%.

The first change comes about by removing blocked shots for and against, and not all teams block as much, or shoot in ways where shots are blocked as much. Having your shots blocked a lot can mean you shoot through traffic a lot, and isn't necessarily ‘bad’.

The change to really poor results with Expected Goals is largely driven by shot location, the biggest part of Expected Goals after shot volume itself. The process of an Expected Goals model is to take every unblocked shot, and weight it for quality according to location, type or other factors depending on the model. Individual shooter ability is not part of hockey Expected Goals models. The result is the value of that shot off the stick of an imaginary league-average player.

What we could clearly see from various heatmaps or just numerical analysis is that the Leafs to date have shot a lot from the points and also that the Leafs defenders have been taking a higher proportion of the shots than in past years. These aren’t the same things. Forwards can shoot from the points and defenders can shoot from the net front.

The Leafs shooting to date in terms of proportion of total shots on the ice looks like this:

HockeyViz as of November 22, 2019

You want to concern yourself with the horizontal position of each player. The vertical is shooting percentage on the season. So, you can see that Auston Matthews is at over 20% of the total shots taken while he’s on the ice, but the biggest puck hog has been Ilya Mikheyev. Tyson Barrie shoots more than any other defender by this measure, while Cody Ceci lets others do the shooting.

Now, let’s look at last night’s game. There were a lot of shots, and a very high pace of play. The Leafs finished with 65% Corsi For, which means they were in the offensive zone most of the time, and the Corsi For per 60 minutes was a huge 88. That can happen in a single game. It won’t happen in all games.

This is the same principle as the chart above. All shots as a percentage of on-ice shots for the player at five-on-five.

Maple Leafs vs Arizona Coyotes Nov. 21, 2019. iCF as a % of CF
Natural Stat Trick, all data is five-on-five unadjusted.

Auston Matthews had a great night. Mikheyev shot the puck the most of anyone on his line (which was usually John Tavares and Zach Hyman) and Nic Petan wisely did the shooting for the fourth line.

Jake Muzzin shot the puck a lot, over 20% of the shots were his when he was on the ice. Justin Holl was just behind him, and both Travis Dermott and Morgan Rielly shot a lot. Interestingly, although he said that was how he would play all the time from now on, Tyson Barrie did not shoot much at all, less than the perennial puck-shy Cody Ceci, and much less than his norm.

Now let’s have a look at how that translated into offensive pace and quality mixed together in Expected Goals:

Maple Leafs vs Arizona Coyotes Nov. 21, 2019. ixGF as a % of xGF.
Natural Stat Trick, all data is five-on-five unadjusted.

And now we see, starkly, why we talk so much about limiting defender shooting. In last night’s game, the locations those defenders shot from were so poor that the value of their on-ice share of the offence was inline with the rookie fourth liner in his second game, a player who played with a centre who never once shot the puck all night and who started most of his shifts in the defensive zone.

Tyson Barrie can absolutely play like that from now on. That is excellent discernment in shooting, and he got a lot of bang for his shooting buck, while letting the better shooters carry the day. Morgan Rielly did not have a good game, and we should consider very seriously that in the rush to decide Barrie or his usage was “the problem” that his usual partner, Jake Muzzin, is shooting a lot of those meaningless point shots.

Meaningless is actually an unfair term. Point shots are not bad in and of themselves. They can get the puck in play, start a net-front scramble, and result in better offence. Whatever the Leafs were doing all season wasn’t resulting in that, and there’s a chicken and egg argument that asks if the point shots were the end result of offensive cycles that failed, or were they the cause. But too much defender shooting is not a good thing because most of the time, they won’t be from some aggressive play where they joined the rush.

Justin Holl, playing more minutes than usual, shot the puck a lot to very little benefit. He was acting just like Muzzin, his partner for most of the game. And the forwards those two shooters were on the ice with most? The Tavares line for about half of their time on ice . So by the time Mikheyev took his shots, Holl and Muzzin had theirs, and Hyman also got his in, Tavares was left with only an even 1/5 of the shots for himself. And I don’t know about you, but I want JT to hog the puck more like Matthews does. Just look at how well he shot when he managed to get it away from a defender! He needs to be the go-to player on his line, and he should be taking passes, not just hustling for rebounds.

That’s why we keep talking about defencemen and their shot rates.

Sheldon Keefe’s activated defenders and his offensive system is just beginning, but there is a good reason for caution about plans to have all those puck-moving defenders handling the puck a lot more. It’s going to work out great if they create the opportunities to pass instead of shooting. It’s going to be more of the same poor shot quality washing out the effectiveness of all the heavy pace if they don’t. Game one was a mixed bag where the total domination by the Leafs in the game covered over some flaws in the overall offensive pattern.