- Joined
- Jul 28, 2004
- Messages
- 130,165
When the Kings arrived home earlier in the week, much of the talk was about the winning momentum they found on the latter half of their just completed four-game road trip through the Northeast. They had a three-game winning streak in hand and life was somewhat good again. However, let’s circle back to the one significant problem from the trip, a 7-0 blowout loss in Buffalo, where 11 different Sabres recorded at least one point and David Rittich was pulled after letting in five goals on only 17 shots.
So, what happened?
Those following the Kings for any amount of time this season have probably noticed that they almost always outshoot their opponents, win or lose. This game was no different, with LA outshooting Buffalo 33-24.
What is Corsi?
Don’t give up just yet. The math will be fairly easy.
When it came to shot attempts (SAT) — which includes blocked shots, shots that missed the net, and shots on goal — the Kings nearly doubled Buffalo’s 47 SAT with 83 of their own. It’s important to start here because shot attempts are what’s used to calculate one of the most well-known advanced stats in hockey, Corsi.
Named after goalie coach Jim Corsi, this stat is fairly simple to figure out. It is just the ratio of Corsi For (shot attempts for) to Corsi Against (shot attempts against). A Corsi value above one is indicative of taking more shot attempts than the opponent, and a value below one is indicative of the opponent taking more shot attempts.
In this specific game against Buffalo, the Kings had a team Corsi value of 1.77, which means they took a lot more shot attempts than the Sabres.
Corsi (C) = Corsi For (CF) / Corsi Against (CA)
Note that CF and CA are the same as Shot Attempts For and Shot Attempts Against.
What is Corsi For Percentage?
Now, let’s look at Corsi For Percentage on an individual basis. Corsi For Percentage (CF%) is Corsi For divided by the sum of Corsi For and Corsi Against. Putting this on an individual basis means the shot attempts used in making the calculations only come from when that player is on the ice.
If Trevor Moore is on the ice for 15 shot attempts for and 10 shot attempts against throughout the game, his CF% would be 15 divided by the sum of 15 and 10, which gives us 60%. Generally, if a player contributes more at one end of the ice than the other, their CF% will be around 50%, but if they are creating more shot attempts while also preventing opposing shot attempts, their CF% will increase.
The league leaders in CF% according to MoneyPuck.com as of Feb 19 were Matthew Tkachuk and Evan Bouchard, both at 66%.
For the game in Buffalo, the Kings only had two players with a CF% below Buffalo’s highest individual CF%, Matt Roy and Trevor Lewis — each with a CF% of 52.4%. The Sabres highest individual CF% was J.J. Peterka at 53.6%. The Kings had four players with a CF% over 70%: Pierre-Luc Dubois (70.4%), Quinton Byfield (70.7%), Drew Doughty (71.4%), and Alex Laferriere (73,9%).
Corsi For % (CF%) = CF / (CF + CA)
What does this mean?
The story this tries to illustrate is that Los Angeles was attempting to shoot the puck a lot throughout the game, but Buffalo was more selective with the shots they were taking.
Looking at the shot charts below, it is clear that the Sabres were taking much more dangerous shots, while the Kings were shooting from all over the ice. This is not always a good thing, and teams should usually be trying to prioritize shot quality over shot quantity.
Shot Chart from Hockey-Reference
While Corsi is great for telling the story of the quantity of shots, it should not be utilized alone and is more powerful when paired with shot charts and Expected Goals models to gain a full understanding of the shots being taken in a game.
Although the Kings left Buffalo unhappy and beaten, they were able to adjust as they headed to New Jersey, where they began their current four-game winning streak, including a victory over Columbus at home on Tuesday.
RELATED CONTENT:
Follow @mayorNHL
Continue reading...
