For those who already know Corsi Stats, there is a breakdown of some notable Blues Corsi ratings at the bottom of this article.
Tilting the Ice in the Right Direction: Corsi Stats
Corsi ratings (created by, and named after, former Blues goalie coach, Jim Corsi) measure the quality of team puck possession or a skater’s on ice possession metrics. Team and skater Corsi ratings are negatively affected when shot attempt against (SATA) is allowed. Vice versa, Corsi ratings are positively affected when shot attempt for (SATF) is made. A Corsi for percentage (CF%) at 50.0% or better is determined to be good. A CF% above 50.0% equates to the majority of shots heading towards the opposing net minder.
A player’s or team’s CF% is calculated with this equation:
[SATF / (SATF – SATA)] X 100 = CF%
Relative Corsi ratings compare a skater’s possession quality to the rest of the team. This percentage reflects how positively or how negatively a skater impacts the team’s puck possession while on the ice. You can also think of this as how well the team performs with or without the player, sort of like baseball’s Wins Above Replacement (WAR) statistic. A relative Corsi for percentage (CF% rel) greater than 0.0% is determined to be good. A skater with a CF% rel better than 0.0% positively influences team puck possession.
A player’s CF% rel is calculated with this equation:
On ice Corsi for % – Off ice Corsi for % = CF% rel
The Corsi rating method is not without flaws. For example, a skater who takes a higher amount of defensive zone starts than offensive zone starts will, by nature of the game, usually be on the ice for more SATA than SATF. On the other hand, a skater who takes a higher amount of offensive zone starts than defensive zone starts will usually be on the ice for more SATF than SATA. Considering ice zone starts, a skater’s Corsi rating can be seen as better or worse than the actual number.
Significant Corsi Ratings of Blues Skaters
The Blues currently have ten skaters (minimum ten games played) that have a CF% within 0.5% of 50.0% or better. All of these ten skaters also have a CF% rel above 0.0%. The four most impressive skaters, relative to their Corsi stats, on this list are Dmitrij Jaskin, Vince Dunn, Brayden Schenn, and Jaden Schwartz.
Dimitrij Jaskin holds a CF% rel of 10.5% and takes 64.7% of his starts in the defensive zone. Therefore, Jaskin significantly improves the team’s puck possession while most of his ice time begins in the defensive zone. Vince Dunn holds a CF% rel of 5.9% and takes 60.5% of his starts in the offensive zone. These are great stats for any skater, but they are exceptional numbers for a rookie. Dunn exhibits a fantastic hockey IQ in his timing for pinching in to keep the play alive and when he effectively joins the rush. Brayden Schenn and Jaden Schwartz are often line mates and have nearly identical possession metrics. These two hound the puck like dogs on raw meat, and can quickly make plays to allow high quality shot attempts. Most noteworthy, Schenn and Schwartz combine for 11 goals and 28 points in this young season.
CF%: 57.4% CF% rel: 10.5%
CF%: 53.6% CF% rel: 5.9%
CF%: 53.0% CF% rel: 5.2%
CF%: 52.8% CF% rel: 5.0%
CF%: 51.2% CF% rel: 1.9%
CF%: 50.5% CF% rel: 1.6%
CF%: 50.4% CF% rel: 1.4%
CF%: 49.9% CF% rel: 0.8%
CF%: 49.9% CF% rel: 0.7%
CF%: 49.8% CF% rel: 0.5%