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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    Buffalo’s depth on defense is dwindling

    BUFFALO, NY - OCTOBER 18:  Josh Gorges #4 of the Buffalo Sabres skates against the Boston Bruins at First Niagara Center on October 18, 2014 in Buffalo, New York.  (Photo by Jen Fuller/Getty Images)
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    The Buffalo Sabres aren’t known for their depth on defense, so when they have to deal with injuries at that position, things can get complicated.

    Well…I guess things are about to get complicated.

    On Sunday, the Sabres announced that Josh Gorges (pictured) will miss “weeks” because of a non-displaced fracture in his foot. The injury occurred after he blocked a shot in Thursday’s game against the Rangers.

    Besides Gorges, Buffalo is also without Zach Bogosian and Dmitry Kulikov.

    Bogosian has been out since Nov. 3 with sprained ligaments in his knee, and he’s still 10-to-14 days away from getting back into the lineup.

    The news is a little better for Kulikov, who returned to practice on Sunday. He’s missed 11 games because of a back injury he suffered in the preseason. He tried playing through it, but obviously he was still in some discomfort.

    “Kulikov has now skated two days with some physicality and now been skating for seven days,” coach Dan Bylsma said, per the Buffalo News. “Hopefully, that means we’ll see him in practice soon – in the next week hopefully.”

    Now, some of the replacements for these guys are starting to get hurt.

    Taylor Fedun missed Sunday’s practice and it’s unclear if he’ll be able to play against the Capitals on Monday night. If he can’t go, Buffalo will need to call someone up from the minors.

    Things got so wacky last week that the Sabres called up Brendan Guhle from junior on an emergency basis. By rule, he can stay on the roster as long as he keeps playing. Once he stops playing, the emergency tag is removed and he has to go back to his junior team.

    Guhle, Rasmus Ristolainen, Jake McCabe, Cody Franson and Justin Falk are the healthy defensemen on the roster right now.

    Goalie nods: Dubnyk looks to continue dominance of Oilers

    CHICAGO, IL - APRIL 07:  Devan Dubnyk #40 of the Minnesota Wild celbrates a win over the Chicago Blackhawks at the United Center on April 7, 2015 in Chicago, Illinois. The Wild defeated the Blackhawks 2-1.  (Photo by Jonathan Daniel/Getty Images)
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    Playing against your old team is always special, but Devan Dubnyk takes it to another level when he goes up against the Edmonton Oilers.

    The Oilers drafted Dubnyk in the first round, 14th overall, in 2004 and he spent parts of five seasons with them.

    Since leaving Edmonton in 2014, he’s won six of seven games against his former team.

    To make matters worse for the Oilers, his individual stats are better against them than they are against any other team in the league. He has a  1.28 goals-against-average and a .949 save percentage in those seven games.

    His numbers in 2016-17 aren’t as good as his career numbers against Edmonton, but he still has a fantastic 1.67 goals-against-average and a .946 save percentage this season.

    Like the Wild, the Oilers played last night, as they won an OT decision against the Ducks.

    Cam Talbot played in that game, so they’ll opt to start backup goalie Jonas Gustavsson tonight.

    Elsewhere… 

    Ben Bishop turned in a solid performance against the Capitals last night, but the Lightning still haven’t announced who their starter will be this afternoon. Cam Ward is likely to get the nod for the Hurricanes.

    –The Flyers and Predators both played afternoon games yesterday, and neither side has indicated who will start. Don’t be surprised if it’s Steve Mason against Pekka Rinne.

    Jared Coreau made his NHL debut for Detroit yesterday, so look for Petr Mrazek to get the call tonight. Jaroslav Halak is the probable starter for the Islanders.

    –Look for Connor Hellebuyck to be between the pipes for the Jets, but that hasn’t been confirmed. With Corey Crawford hurt, don’t be surprised if Scott Darling gets his second start in two nights for Chicago.

    –The Ducks will give backup Jonathan Bernier the start in Calgary. The Flames will continue to ride Chad Johnson.

    Flames get Johnny Gaudreau back way ahead of schedule

    CALGARY, AB - APRIL 5: Johnny Gaudreau #13 of the Calgary Flames in action against the Los Angeles Kings during an NHL game at Scotiabank Saddledome on April 5, 2016 in Calgary, Alberta, Canada. (Photo by Derek Leung/Getty Images)
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    Some good news if you’re a fan of the Calgary Flames.

    Johnny Gaudreau, who missed 10 games with a finger injury, will be back in their lineup for Sunday’s game against the Anaheim Ducks.

    The Flames forward was injured in a game against Minnesota on Nov. 15 (he was slashed by Eric Staal), and after he underwent surgery, the team announced that he’d be out six weeks.

    In the end, he missed less than three weeks of action.

    “I’m ready to play,” Gaudreau said, per NHL.com. “I think the finger’s healed up pretty well there. I’m just excited to get things going here.

    “I think they did a great job with my finger and we did a great job rehabbing it. They keep tell me it’s going to be harder to break the nine other fingers than to re-hurt this one. It feels good. It feels good when I shoot. I’m excited to finally get out of there.”

    He’ll be playing with some added protection, as Calgary’s equipment manager made this glove for him:

    Before Gaudreau got hurt, the Flames had a 6-10-1 record. But thanks to improved team play and some strong performances from goalie Chad Johnson, they managed to go 6-3-1 in, while Gaudreau was out.

    The 23-year-old has five goals and six assists in 17 games, but he had scored three goals in three games before getting hurt.

    Related:

    Gaudreau injury a reminder as to how star players are treated

    Boudreau: Flames made “mountain out of a molehill” over Gaudreau slash

    Garret Sparks plays for first time since being suspended by Maple Leafs

    TORONTO, ON - NOVEMBER 30:  Garret Sparks #31 of the Toronto Maple Leafs gets set to face the Edmonton Oilers in an NHL game at Air Canada Centre on November 30, 2015 in Toronto, Ontario, Canada. The Maple Leafs defeated the Oilers 3-0. (Photo by Claus Andersen/Getty Images)
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    Garret Sparks made waves for all the wrong reasons last week, as he was suspended by the Maple Leafs for remarks he made on social media.

    Sparks officially made his return on Saturday night in the Marlies’ 3-2 loss to the Hartford Wolf Pack. He stopped 27 of 30 shots.

    “It’s been a lot to deal with. I understand what I did,” Sparks said, per TSN.ca. “[The incident] wasn’t me. That’s not who I want to be known as, it’s not the image I want my reputation to have.

    “I should know the difference between what I can and can’t say. It’s just holding myself to a higher standard of professionalism.”

    The 23-year-old actually returned to the team on Tuesday, but didn’t play until yesterday.

    With Leafs goalie Frederik Andersen dealing with an illness, the Leafs recalled Antoine Bibeau, which opened the door for Sparks to make his return.

    Sparks has been limited to just five AHL games this year, but he was between the pipes for 17 NHL games in 2015-16.