'Tape to Tape' is a weekly feature I hope to expand and improve upon as the year progresses. This is my first foray into the big bad wolf the hockey world calls 'Analytics', so be gentle. If you're rude, at least bring questions and insights with you.
Today I'm gonna focus on the Minnesota Wild game on 1/9/2016. Over time, these posts will have two to three games nestled together for more information, but a) I wanted to get this post up quick for early feedback and b) I suspect that the Wild game is indicative of the broader struggles this Dallas team has experienced. If this looks TL;DR don't worry. They'll be shorter in colder bandwidth, but since there are still people that may question the value of analytics, I feel like I have to say a few things first.
Corsi/Fenwick: What They Are and Why They're in Important in Two Simple Paragraphs
Some people may still be a little unfamiliar with "advanced stats", and that's okay. But if you're afraid, don't be. Corsi and Fenwick are just the dust sweepers against that nagging question during games, "wait a minute Mr. Broadcast Expert, we've taken way more shots than that!". Both tally all shots taken, regardless of whether or not the shot required the goalie to make a save. Corsi tallies all types of shot attempts to approximate possession. Fenwick tallies all types of shot attempts minus blocked shots to approximate scoring chances, in part because a blocked shot indicates possession, but not an actual scoring chance. So there's a subtle but vital distinction.
Everything else kind of helps contextualize things, like where the player must start (zone starts), how productive they are relative to their teammates, how productive they are relative to their competition, and so forth. Is all of this enough? Of course not. Any culture of research experiences growing pains. It's why physicists can tell you what the atom is doing, and what a hockey puck is doing, but can't quite explain why their behavior is so different (string theory's dilemma in a nutshell). Or why neurology can tell you about the 100 billion neurons in your brain, but not the important non electrical cells that outnumber your neurons. Like the atom, or the neuron, Corsi and Fenwick are just reference points for understanding, not an understanding itself. P.S. Don't forget that this very site has accommodated you in this regard, enough so that even an art major can understand.
'Beyond Corsi' and the Minnesota Wild @ Dallas Stars 1/9/2016
Just what the heck is the problem in Big D? Documenting shot attempts probably aren't enough. Granted, this isn't news to anyone in or outside the #pocketprotectorcrowd. But even David Johnson (to the surprise of no one he often scuffles with) has expressed his misgivings.
For the most part hockey analytics has developed by looking at what team statistics correlate well with team success and then transferring those observations to player evaluation (i.e. Corsi correlates with winning so good players should have good Corsi numbers as well). While transferring what we know from the team level to the player level has merit one problem I have is we have largely treated players as a homogeneous group. Sure we often often look at forwards and defensemen separately but we haven't gone any further than that. We haven't look at offensive defensemen and defensive defensemen separately or offensive and defensive forwards separately.
So...what the heck makes me an expert? Zero. My major was philosophy. Done laughing? Cool, me too. But fear is not on my side for today. So because I wasn't satisfied with shot attempts, I went to passing. After all, 'Corsi' and 'possession' are not synonymous. A shot attempt indicates possession, but doesn't define possession.
What kind? Well, all of them. I went back to the Wild game and documented the following possession events at Even Strength: passes to a winger (PTW), passes to the center (PTC), passes to a defensemen (PTD), dump ins (DPI), (successful) passes up the rim (RIM), whether or not the player skated with possession through the zone (SWP), forced turnovers (FTO), and unforced turnovers (UTO) across all three zones.
The latter two require some clarification. A forced turnover refers to any turnover that resulted from a poke check, hit, or the threat of either*. An unforced turnover refers to any turnover that resulted from an errant pass or loss of possession without the presence of a poke check, hit, or threat of both. You could argue that dump ins are a form of unforced turnovers, but I think it's important to distinguish a mistake (unforced turnover) from a decision that is typically more neutral. Dump ins can be the product of line changing. And strategically, they can be signs of adjustment. After all, carrying the puck in may be a nice sign of possession, but it's also an opportunity to reverse possession, and some teams are better at countering than others.
With that out the way, here's a cliffs notes version of the Wild game. Shot Attempt total was 61 to 40 in favor of Dallas. High Danger Scoring Area chances were 6 to 15 in favor of Minnesota. Top 5 in On Ice Corsi differential was Johnny Oduya, Valeri Nichushkin, Jason Spezza, Jason Demers, and Jamie Benn. Bottom 5 was Cody Eakin, John Klingberg, Patrick Sharp, Tyler Seguin, and Colton Sceviour.
Getting Over-Aggressive in the Offensive Zone
The Dallas Stars love the word 'aggression'. And they also love the word 'possession'. It's something emphasized in their video review sessions where Ruff explicitly encourages players not to dump the puck in, but to look for the efficient pass to maintain possession. However, lately they've been plenty of the former, but less of the latter.
Using the aforementioned passing key, I tabbed 89 'passing/possession events' in the Offensive Zone. 42 Percent of those events resulted in either forced or unforced turnovers. If you want to see who the culprits are, here's a look:
Again, just one game, but if you've ever complained about Nuke getting tunnel vision in the corners, there's a visual. This isn't an indictment on Nuke though. While it's not great to see that many, it indicates possession of the puck, and he's impossible for opponents to hit or poke check successfully. The real problem stems from Dallas trying too hard to keep the puck in the offensize zone. Granted, this is a bit of a broken play, but watch as Goligoski's unforced turnover becomes a breakaway.
This is right after Klingberg pinches to steal possession of the puck, which he does successfully, to record a shot. Yes, Goligoski needs to take a better shot but Klingberg and Benn (that flashing bit of victory green you may miss if you blink) need to communicate to one another. Either Benn needs to make a conservative read, or Klingberg needs to stand point (which he obviously doesn't do since you can see him trying to pinch down low once more).
Here's another example of reading with typos. Demers is making an aggressive read and play to keep the puck in. There's nothing inherently wrong with this. But it's a good example of Dallas' trying to maintain possession too aggressively. However, this forced turnover doesn't have to turn into a near breakaway (it doesn't, believe it or not, in part because Oduya is in great position). Look at how low the forwards (Spezza, Nuke, and Janmark) are. Just to look at one more:
This is more of a bad play on Spezza's part. This rush happens because Radek Faksa (the forward sneaking into frame) causes a neutral zone turnover. Thankfully Jokipakka and Oleksiak (the defensemen not in the picture) are where they need to be, but they have to deal with an odd man rush because the forwards assemble so low too quickly.
Noise in the Neutral? You Bet!
I won't talk much about the Neutral Zone because I don't know what the numbers are telling me. The neutral zone is typically the barrier between a successful exit and a successful entry. It's not as neutral as you might think though.
For example, there were more possession events in the Neutral Zone than in the Offensive Zone. 101 to 89 in fact. But only 12 Percent of passing or possession events resulted in forced/unforced turnovers. Cody Eakin had the most unforced turnovers (3) in the neutral, and Mattias Janmark and Jason Spezza had the most instances of skating through the entire zone with possession at 4 a piece. Oduya was the most likely to dump the puck in from the Neutral (with four), Eakin was most likely to pass to a forward, and John Klingberg was the most likely to pass to his defensive partner.
My guess is that Dallas' forward core is pretty good at either skating through the zone, or playing tic-tac-toe where their teammates are in closer proximity.
Dallas' "Russia From Sochi" Problems in the Defensive Zone
The defensive zone was, as you might expect, the most active in terms of 'events'. I counted 167 total, and 20 Percent of those events resulted in either forced, or unforced turnovers. Demers and Klingberg led the way in errant passes. Again, you have to have the puck to begin with in order to turn it over, so it's no surprise that some of the better possession players are also turning it over. Oduya was most likely to pass it to his defensive partner, Klingberg was most likely to get it to the center, and Demers was most likely to pass it to a winger. Alex Goligoski was surprisingly, most likely to skate it out of the zone.
When you tally up all the passes to the forwards from the defensive zone, the forwards are receiving said passes 36 Percent of the time. Is that the norm? Good? Bad? Average? No clue.
But the defensemen seem to make passes while flat footed fairly often. There's nothing wrong with the following play. It's a polite exchange between two defensemen. But there's not a whole lot of movement back there.
Even though the forward support is there, it's important to note how much space sits between the forwards and the defensemen once the rush begins. Compare that breakout to an example of Minnesota's:
Now, the two plays are obviously different. Minnesota is responding to forechecking pressure while Dallas is under no pressure at all. But it's something I saw more than once from both teams; Brodin moving his feet with Dumba in sync, and a forward down low helping out. Meanwhile, Dallas' defensemen would look for the long pass, or a rim across the boards. As you can see, teams anticipate the latter:
In hockey lingo, this breakout is called a quick-up; a breakout under pressure where the defensemen looks for the immediate option on the strong side boards. Here Oduya tries the team's go to play, and Minnesota reads it like a twitter trend. This isn't an indictment on team traits though; every team relies on some foundation of set plays and patterns that speak to their strengths. The efficiency trick is to take greater advantage of it when it works, and conceal its limitations when it doesn't. Nonetheless, there's still the real issue of lacking motion in the defensive zone.
In 2014, everyone wondered how a team with Alex Ovechkin, Evgeni Malkin, Pavel Datsyuk, and Ilya Kovalchuk (all at once, mind you) could fail to score goals. That's what many analysts tried to figure out when Russia goofed in Sochi. Justin Bourne articulated well what Russia's problem was; bad gaps and inertia in the defensive zone:
When you come up the ice as a five man unit you can move the puck like it's ultimate frisbee. Those short passes allow you a multitude of lanes to choose from, which makes it easier to force your opponent to have to rotate, and making guys think and move is the best way to create holes. You've also got the play in front of you, so you can make the choice to rush the puck wide or move laterally depending on the gap you're allowed. And quite simply, you're better off with the puck inside traffic than skating into it and then trying to acquire it via a long pass. If you can avoid making your opponent's job easier, you should.
This is just one game so it's important to keep that in mind moving forward. 23 Percent of Dallas' passing or possession plays through all three zones resulted in either forced or unforced turnovers, but that percentage is buffed by a gulf in how often they turn it over in the offensive zone. Whether or not that's the norm is anyone's guess, but I'd imagine that difference in turnover rates in the opponent's zone factors into why Dallas gives up so many high danger scoring chance areas (currently at a -33 differential) in particular; they have a much higher turnover rate in the offensive zone, and it seems to really affect their positioning upon resetting.
Some of this is just the month being very unkind. Jordan Dix over at the Hockey Writers recently looked at how their second periods were:
The Stars have a 0% even-strength shooting-% in the second period so far in 2016. That's right, they have yet to score a second-period goal at even strength. Their PDO at even-strength in the second period in 2016 is 85.7. No team is even close to that number.
Anyway, going forward, I'll try to nestle multiple games together. Perhaps I can even have a full database of this season once the summer rolls around. There are lot of things to document that I haven't even thought of. For example, how many times did Dallas gain possession of the puck off a rebound? How many times did the opponent gain possession? Feel free to email me any ideas moving forward.
*The word 'threat' may seem a little too abstract, but it's essentially as meaningful as 'forechecking pressure' and 'taking away passing lanes' so I think it warrants the distinction.
Big thanks to Josh Lile for the Gifs.