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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    BREAKING: Flames fire head coach Bob Hartley

    Calgary Flames head coach Bob Hartley gives instructions during the third period of an NHL hockey game against the Pittsburgh Penguins in Pittsburgh, Saturday, March 5, 2016. The Flames won 4-2. (AP Photo/Gene J. Puskar)
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    The Calgary Flames have decided to move on from head coach Bob Hartley. The team made the announcement via their Twitter account on Tuesday morning. Associate coach Jacques Cloutier has also been informed that he won’t be back next season.

    Hartley and the Flames surprised many last year when they won 45 games and made the postseason. Hartley was awarded the Jack Adams Trophy as the league’s top coach.

    What a difference a year makes. Unfortunately for the Flames, they won just 35 games in 2015-16 and finished 26th in the overall standings.

    More details to come.

    Kris Letang will have a hearing for hit on Marcus Johansson

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    Many expected it to happen and now it has. The NHL’s Department of Player Safety confirmed that Penguins defenseman Kris Letang will have a hearing for his hit on Caps forward Marcus Johansson in Game 3.

    After Brooks Orpik was suspended three games for this hit on Olli Maatta in Game 2, many people are expecting a similar outcome for Letang. It’s important to note that there are certain similarities between the two hits, but there are also some key differences.

    Both victims definitely took shots to the head, there’s no doubt about that, but to say that the hits are identical isn’t accurate. First, although Letang’s hit appears to be late (0.6 seconds after the puck is gone is considered late), it isn’t as late as Orpik’s hit on Maatta. Another key factor to consider is that unlike Maatta, Johansson returned to the game.

    Letang was given a two-minute penalty for interference on the play.

    TSN hockey insider Bob McKenzie breaks it down perfectly:

    A decision is expected to be made later on today.

    Here’s your Stanley Cup playoffs schedule for tonight

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    The Stanley Cup playoffs continue with three games on Tuesday night. You can catch tonight’s games via the NBC Sports Group’s television and digital platforms.

    Tampa Bay at NY Islanders (7:00 p.m. ET)

    The TV broadcast of Game 3 will be on NBCSN. To stream the game using the NBC Sports Live Extra app, click here.

    San Jose at Nashville (9:00 p.m. ET)

    The TV broadcast of Game 3 will be on the USA Network. To stream the game using the NBC Sports Live Extra app, click here.

    Dallas at St. Louis (9:30 p.m. ET)

    The TV broadcast of Game 3 will be on NBCSN. To stream the game using the NBC Sports Live Extra app, click here.

    Here’s some reading material to get you ready for tonight’s action:

    Lightning strikes: Bolts even series with Islanders

    The Sharks are the only team to grab a 2-0 series lead in the second round

    Seguin resumes skating in Dallas, Ruff notes ‘they have flights to St. Louis every day’

    PHT Morning Skate: Adam Henrique wants to make NHL 17 great again

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    PHT’s Morning Skate takes a look around the world of hockey to see what’s happening and what we’ll be talking about around the NHL world and beyond.

    Martin Jones is a calming presence in the Sharks’ net. (Sports Illustrated)

    –The Rangers should go after Blues defenseman Kevin Shattenkirk. (The Hockey News)

    –Some people have pretty wild hockey tattoos. (BarDown)

    –Watch the highlights of last night’s game between the Penguins and Capitals. (Top)

    –A great piece on how Bruce Boudreau impacted the Ducks and Capitals. (Sportsnet)

    –It should be an interesting off-season for the Anaheim Ducks. (Daily Breeze)

    Adam Henrique is a funny guy. He took to Twitter to try and get himself on the cover of NHL 17: