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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    The Buzzer: Golden Knights shine, gold from Subban

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    Player of the Night: Roberto Luongo, Florida Panthers.

    It hasn’t been the easiest start to the season for Twitter legend Roberto Luongo, nor has it been for the Twitter debate generators known as the Florida Panthers.

    Bobby Lou hasn’t been healthy at times, making it easy to ignore that even at 38, he’s quietly managed a save percentage that climbed to .931 after today’s outstanding performance against the Toronto Maple Leafs.

    Luongo made 43 out of 44 stops to help Florida edge Toronto in a 2-1 shootout win, to the amusingly over-the-top celebration of the Panthers, who might have done so because there were probably a ton of Maple Leafs fans in the house:

    Nick Bjugstad won the game with this saucy shootout score, by the way:

    Honorable mentions go to tonight’s other standout goalies, plus Nathan MacKinnon, who received plenty of praise here.

    Fight of the Night: William Carrier vs. Mike Liambas.

    Is it fair to call this fight “methodical but entertaining?”

    Quip of the Night: P.K. Subban, always entertaining, though he should reduce the height-shaming.

    Pest of the Night: Nazem Kadri?

    Highlight of the Night: John Tavares continues to impose his will, this time setting up the Islanders overtime-winner:

    Factoids of the Night

    Another milestone for the Vegas Golden Knights, who lead the Pacific Division:

    Brock Boeser is another worthy mention for player of the night, as the young Canuck keeps scoring and scoring, this time helping Vancouver beat Pittsburgh (again).

    Connor McDavid continues to impress, and maybe shuts up a critic or two for one night:

    The Canadiens? Well, at least they got a point.

    Scores

    Wild 5, Sabres 4
    Oilers 6, Red Wings 2
    Panthers 2, Maple Leafs 1 (SO)
    Bruins 3, Devils 2 (SO)
    Islanders 4, Flyers 3 (OT)
    Canucks 5, Penguins 2
    Capitals 5, Senators 2
    Rangers 6, Hurricanes 1
    Blue Jackets 1, Flames 0 (OT)
    Lightning 3, Blackhawks 2 (OT)
    Predators 3, Canadiens 2 (SO)
    Avalanche 3, Stars 0
    Sharks 3, Coyotes 1
    Golden Knights 4, Ducks 2
    Jets 2, Kings 1

    James O’Brien is a writer for Pro Hockey Talk on NBC Sports. Drop him a line at phtblog@nbcsports.com or follow him on Twitter @cyclelikesedins.

    Looks like Nathan MacKinnon is going from star to superstar

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    Look, it’s not like Nathan MacKinnon has ever really been a “bad” player.

    The Nova Scotia-born speed demon carried two 20+ goal seasons and three 50+ point campaigns into 2017-18, which in the tough-to-score NHL, is nothing to sneeze at. This is especially true since the Colorado Avalanche have frequently asked him to do a lot; Sportsnet’s Andrew Berkshire notes that he’s faced some of the toughest assignments of any centers in recent years.

    Still, there was growing concern that the 22-year-old might not make that extra step from “star” to “superstar.” That’s especially true if his shooting skill really was an issue, as it seemed to be in three straight seasons where he shot under 10 percent (and considering his 8.4 career average).

    Well, through the first quarter of this season, it seems like MacKinnon is “finally” making that next step, and making us feel silly for worrying too much about a guy who’s still just 22.

    (Heck, he’s not even an old 22. MacKinnon’s birthday came on Sept. 1.)

    Much like the Avalanche as a whole, MacKinnon’s gone from discouraging in 2016-17 to encouraging so far, and he’s probably the biggest reason to feel happy in Colorado … beyond the Matt Duchene headache being resolved, and depending upon your lifestyle, certain perks.

    Wednesday was the latest reminder that the Avalanche aren’t mere pushovers, and that MacKinnon is making that leap we’ve been waiting for to join the best-of-the-best.

    The tremendously fast, increasingly versatile center collected assists on every Avalanche goal as they beat the Dallas Stars 3-0 on Wednesday, improving Colorado’s record to 11-8-1. This actually makes for quite the logjam at “last” in the Central, with four teams at 23 points, and the Avs hold at least a game in hand on the Blackhawks, Stars, and Wild. They’re not far from being a wild card team, either.

    Considering the fact that the Avalanche were one of the worst teams of the salary cap era last season with an almost unthinkable 46 points, and MacKinnon languished with 16 goals, this should put a big smile on GM Joe Sakic’s face.

    But, again, it’s something fans of the sport as a whole should appreciate.

    With tonight’s three assists, MacKinnon now has 25 points in 20 games. This places MacKinnon in a tie for 12th in the NHL in scoring with a pretty illustrious group: John Tavares, Blake Wheeler, and Mark Scheifele.

    To me, the number that’s maybe most heartening is MacKinnon’s 13.2 shooting percentage (seven goals on 53 shots on goal through 20 games).

    It will be interesting to follow this specific trend over the long haul of the season, as he’s firing the puck just a little bit less often; he averages 3.08 SOG for his career according to Hockey Reference, while his current average is 2.65 this season.

    That’s not a massive drop, but it’s actually quite noticeable, and you wonder if MacKinnon is being a little more selective with his shot. Again, it’s a small sample size, so we’ll see if that changes. But if MacKinnon either improves his shooting skill or simply finds a way to inch closer to the 24 goals he scored as a rookie while using his speed and smarts to be a difference-maker in every phase of the game, this could be quite the transformation.

    The Avalanche probably weren’t going to complain about “the old” MacKinnon, but they should be delighted if he ends up being a truly complete star, and one who can flirt with 20-goal, 70-point seasons.

    And you know what? Fans of exciting hockey should be excited about this development, too. Even if he’s using his scary speed and skill to your own team’s dismay from time to time.

    James O’Brien is a writer for Pro Hockey Talk on NBC Sports. Drop him a line at phtblog@nbcsports.com or follow him on Twitter @cyclelikesedins.

    Point gets Lightning extra point against Kane, Blackhawks

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    The Tampa Bay Lightning edged the Chicago Blackhawks – barely – on Wednesday to leapfrog back over the St. Louis Blues for the top record in the NHL.

    The Bolts capitalized on a power-play opportunity in overtime, with Brayden Point scoring the decisive goal in a 3-2 OT win. It was an exciting overtime period, with Point being stopped all in alone earlier in the OT, and the same happening to Patrick Kane on a breakaway.

    Kane had been getting the best of the Lightning earlier in the game, scoring the first two goals of the contest in the first period. Not a lot of players can make plays like this off the rush:

    Then again, few teams can score a goal this pretty, especially while shorthanded:

    Steven Stamkos and Vladislav Namestnikov collected assists on Wednesday, but the top line (including Nikita Kucherov) failed to score a goal, though they created quite a few chances. The best – at least in regulation – came when Stamkos seized an opportunity against the Blackhawks, but Corey Crawford was game:

    Wow.

    Again, both goalies made some big stops. Here’s that Kane miss in OT, with Andrei Vasilevskiy depriving number 88 from a hat trick:

    So, with that, the Lightning hold a one-point standings edge (34 to 33) over the Blues in the early race for the Presidents’ Trophy, and most importantly, gives them a five-point edge in the Atlantic Division. Tampa Bay’s impressive start to 2017-18 is especially notable since they’ve played one fewer game than St. Louis and two fewer than the Toronto Maple Leafs (the second-ranked team in the up-and-down Atlantic).

    Check out the logjam at second-to-last in the competitive Central for Chicago, as of this writing, with these three teams all at 21 games played:

    Dallas Stars: 11-9-1, 23 points
    Blackhawks: 10-8-3, 23 points
    Minnesota Wild: 10-8-3, 23 points

    It has to be a little frustrating for the Blackhawks to see a two-goal lead dissolve, but plenty of teams would struggle to secure such an edge against the powerhouse Lightning. Maybe the Blackhawks will gain some confidence in merely sticking with them (and grabbing a point for their troubles).

    James O’Brien is a writer for Pro Hockey Talk on NBC Sports. Drop him a line at phtblog@nbcsports.com or follow him on Twitter @cyclelikesedins.

    Much-needed response from Oilers vs. Red Wings

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    One win can’t cleanse the palate of a bitter 21-game start, but beggars can’t be choosers, and the Edmonton Oilers really needed a W tonight.

    That’s not to say it would be easy, either, as they faced a rested Red Wings team in Detroit to close off a back-to-back after Tuesday’s humiliating loss to the St. Louis Blues. Edmonton got that sorely needed response, chasing Jimmy Howard and beating the Red Wings 6-2.

    While Connor McDavid (two assists) and Leon Draisaitl (one helper) made their typical impacts, it’s especially heartening for the Oilers to see less-obvious names show up in the box score. Jesse Puljujarvi, Jujhar Khaira, Mark Letestu, and Drake Caggiula ranked among goalscorers, while Ryan Strome collected a pair of assists.

    Any bit of confidence gained, particularly for supporting cast members, could be very important for the fledgling Oilers.

    It doesn’t take long to ruin the party; now at 8-12-2, the Oilers’ 18 standings points still leave them at second-worst in the West.

    Still, all the Oilers can do right now is gradually, slowly dig themselves out of the troubling hole they’ve created for themselves. This won’t be easy, and even this early on, they might need a few other teams to hit a wall.

    But, hey, it’s better than the nothing this team showed last night, right?

    Catch up on Edmonton’s struggles

    Why they’re the NHL’s most disappointing team

    The uncomfortable parallels between McDavid and Jack Eichel

    These struggles are the results of some bad moves from Peter Chiarelli

    James O’Brien is a writer for Pro Hockey Talk on NBC Sports. Drop him a line at phtblog@nbcsports.com or follow him on Twitter @cyclelikesedins.