Jim Corsi: The man behind Corsi numbers

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The hockey world is ages behind “Moneyball” philosophy and Sabermetrics, just to name a few buzzwords associated with the innovative stats championed by baseball writers and stats gurus for years. That isn’t to say that hockey bloggers/writers/fans/front office people are completely turning a blind eye to analysis that goes deeper than goals, assists and plus/minuses, though.

One of the most well-known “new” stats is the Corsi Number, named after Buffalo Sabres goalie coach Jim Corsi (he’s the guy in that photo who’s either short … or maybe standing next to Tyler Myers). To explain the stat (a bit too) simply: it’s basically an alternative to plus/minus in which shots replace goals. Here’s a more detailed description from David Staples’ great story about Corsi (the man and the stat).

Corsi is a plus/minus stat that measures shots directed at net. For example, if the Edmonton Oilers direct 30 shots at even strength at the Calgary Flames’ net in a game, while the Flames direct 45 shots at the Oilers’ net, the Oilers have a Corsi of -15 for the game. People who put a lot of faith in Corsi plus/minus numbers argue that you even if a team loses a stretch of games, but if that team has a strong Corsi plus/minus in each game, it’s an indication that the team really isn’t so bad, that it’s moving the puck to the right end of the ice, that it has territorial dominance, and that the goals will soon come.

This team Corsi number is also broken down and applied to individual players. For example, if Sheldon Souray is out on the ice for 10 shots directed at the Flames’ net, while the Flames direct 15 shots at the Oilers’ net while Souray is on the ice, he’s said to have a Corsi plus/minus of -5.

It’s a fascinating story that is definitely worth the read. I’ll leave you with the stat’s origin story, from Corsi himself.

The traditional way of measuring a goalie’s work load was to look at the number of shots against the goalie faced in a game. But having played goalie himself, Corsi didn’t trust that basic indicator so much. “When I played, I’d finish a game with about 25 shots on goal and I was really tired. I was really very, very tired,” he says.

“When you look at 20 or 25 shots, you say, Well, it’s a light game.’ But if you look at a game, an (attacker) comes down the right side, he’s got the puck, and he turns up the boards, towards the wall, the goalie is not standing on his heels going, ‘Oh, you know, whatever.’ He’s going to bear down, tense up, prepare that this is going to end up as a shot. Now as (the attacker) turns, he (the goalie) has still got to be engaged and wait for the next play.

“You get a 25-shot game, but with all the blocked shots and the increase in blocked shots and the tightness of the defensive zone coverage, the activity of the goalie could almost be like 75 to 100 actions at the net.”

To get a better sense of how much work his goalies faced, Corsi started to use the NHL’s data that tracks missed shots, blocked shots and shots on goal. He added all these together to come up with a goalie’s so-called Corsi number for a night of work. “It’s really just a number that I’ve used for goaltenders to hone in on their fitness and how much activity is actually going on with respect to goaltending.”

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    Measure of revenge: Kings delay clinching efforts for Flames, Blues

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    Deep down, the Los Angeles Kings probably realize that their season will end on game 82. Still, they kept their slim playoff hopes alive on Wednesday night … and managed to spite a team they’re growing to hate.

    OK, maybe the hate is almost totally focused upon Matthew Tkachuk, yet the disdain for that talented-but-tormenting rookie was palpable.

    It didn’t feel like the Kings exacted physical revenge on Tkachuk, but beating his team 4-1 ranked as classic scoreboard vengeance. With that, the Calgary Flames (and by extension the St. Louis Blues) will need to wait to clinch a playoff berth.

    Now, as much as tonight was about Tkachuk, the focus was also on a pugnacious player who once dazzled for the Flames: Jarome Iginla.

    In what might be Iginla’s final visit to Calgary – at least as an active NHL player – he was one of the best players on the ice. His fitting curtain call included a “Gordie Howe hat trick” with a spirited fight, an assist and a goal.

    Seriously, that fight with Deryk Engelland:

    That goal included a bit of luck, but hey …

    Iginla was named the first star of the contest, and cameras captured his big smile in enjoying a special night. For all the nastiness of that game, it was refreshing to see such a heartwarming moment.

    For more on the violence, check out this post on the early stuff and this one on Tkachuk’s missed missile launch on Drew Doughty.

    Kings and Canucks will square off in first NHL exhibition games in China

    graphic via NHL
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    It’s official: the NHL will hold preseason games in China before next season.

    The league made the announcement on Wednesday night: the Los Angeles Kings and Vancouver Canucks will play two exhibitions: one on Sept. 21 (Shanghai) and Sept. 23 (Beijing). How cool is that?

    “It is a privilege and an honor for the L.A. Kings to represent the National Hockey League in China as part of these two games against the Vancouver Canucks,” Kings president Luc Robitaille said. “Growing the game of hockey is something we take great pride in and it is a big priority for our hockey club and AEG as a whole. This will be a once-in-a-lifetime experience for our players and our staff, and we are looking forward to the games taking place in two tremendous facilities in two remarkable cities.”

    The press conference inspired some jokes tonight.

    Some of the best bits came in roping in … Kobe Bryant and David Beckham?

    Alrighty then.

    Click here for more details.

     

    Video: Drew Doughty (mostly) avoids massive Matthew Tkachuk hit

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    Hockey is such a fast sport that it’s probably not so easy to make someone your “target.” Instead, a big hit often comes down to the right combination of circumstance and timing.

    Still, there’s no denying that Matthew Tkachuk is gunning for Drew Doughty (and the Kings are gunning for Tkachuk) on Wednesday.

    Doughty isn’t oblivious to that notion, either, as you can see him avoid what looked like a pretty terrifying hit above.

    We’ve already covered the early violence in this game, and it’s quite possible that there will be more carnage going forward. Stay tuned.

    Blackhawks bolster Central lead, shine harsh light on Penguins’ struggles

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    Blame it on injuries if you want, or emphasize the Chicago Blackhawks’ overall hot finish to the season. Either way, Chicago scorched the Pittsburgh Penguins by a score of 5-1, a contest that felt more or less over by the time the first period ended 4-0 in the Blackhawks’ favor.

    The Blackhawks scored by committee on Wednesday, with Artemi Panarin (goal, assist) and Patrick Kane (two assists) being the headliners. Meanwhile, former Penguin Marian Hossa has quietly climbed to 25 goals on the season.

    Meanwhile, the Penguins limped through this one and have now lost four consecutive games.

    With this result, the Blackhawks look like close to a lock to win the Central Division title. Meanwhile, the Metro crown is virtually unthinkable for Pittsburgh, and the Penguins might also need to accept the likelihood that they may not enjoy home-ice advantage in the first round.

    They’d probably accept that more easily if they can get healthier and get back on track. Wednesday was a little worrisome in those regards.