Tag: Corsi

What Is the Difference Between Corsi and Fenwick?

IHM Knowledge Center

What Is the Difference Between Corsi and Fenwick?

Both Corsi and Fenwick measure shot attempts, but why do analysts separate them, and what does that difference actually show?

Editor: Coach Mark • Updated: April 26, 2026

Short Answer

Corsi counts all shot attempts, including blocked shots. Fenwick excludes blocked shots and only counts attempts that are not blocked.

Full Explanation

Corsi and Fenwick are closely related hockey analytics metrics used to measure puck possession and offensive pressure.

Both track shot attempts, but they differ in one key area: blocked shots.

  • Corsi: shots on goal + missed shots + blocked shots
  • Fenwick: shots on goal + missed shots

This difference changes how each stat is interpreted.

Corsi includes every attempt, which makes it a broader measure of total pressure and puck possession.

Fenwick removes blocked shots, focusing only on attempts that actually reach the net area or pass through defensive layers.

How the Difference Affects Analysis

The inclusion or exclusion of blocked shots changes what each stat represents.

Corsi reflects total offensive activity, including attempts that are stopped before reaching the net.

Fenwick focuses more on attempts that have a chance to become scoring opportunities.

This makes Fenwick slightly closer to measuring offensive effectiveness, while Corsi is more about overall puck control and pressure.

NHL vs IIHF Context

Both Corsi and Fenwick are primarily used in NHL analytics, where detailed tracking allows for accurate measurement.

In IIHF competitions, these metrics can still be applied, but their interpretation may vary depending on data availability and game style.

The core definitions remain the same across all levels of hockey.

Why This Difference Is Controversial

The difference between Corsi and Fenwick is debated because analysts disagree on the value of blocked shots.

Some argue that blocked shots still represent offensive pressure and should be included.

Others argue that a blocked shot does not test the goalie and should not be treated the same as an unblocked attempt.

This creates two perspectives:

  • Corsi values total pressure
  • Fenwick values potential scoring opportunity

Both views are valid depending on what you are trying to measure.

Edge Case: Teams That Block a High Number of Shots

An important edge case occurs when a team blocks a large number of shots.

In this situation:

  • Corsi may show strong offensive pressure from the attacking team
  • Fenwick may show lower offensive impact because many shots are blocked

This reveals something important about the defending team. It shows strong shot-blocking structure and commitment to protecting the net.

This is why using both metrics together provides better understanding than using only one.

IHM Signal System: How to Read Corsi vs Fenwick

To interpret these stats correctly, focus on these signals:

  • Shot suppression: Is the defense blocking many attempts?
  • Net access: Are shots reaching the goal area?
  • Pressure type: Volume pressure vs real scoring threat
  • System structure: Does the team allow outside shots?

Trigger-level rule:

If Corsi is high but Fenwick is significantly lower, the offense is almost always being neutralized by shot-blocking before reaching the net.

This indicates pressure without efficient scoring threat.

IHM Insight: Why This Difference Matters

The difference between Corsi and Fenwick helps explain how defense impacts offense.

A team may appear dominant in total shot attempts, but if many of those attempts are blocked, the real scoring pressure is reduced.

This is why advanced analysis often compares both metrics instead of relying on one.

Mini Q&A

What is the main difference between Corsi and Fenwick?
Blocked shots are included in Corsi but excluded in Fenwick.

Which stat is more accurate?
Both are useful for different purposes.

Why remove blocked shots?
Because they do not reach the net.

Does Corsi measure possession?
Yes, it is often used as a proxy for puck possession.

Should both be used together?
Yes, combining them gives better insight.

Why This Rule Exists

The distinction exists to separate total offensive pressure from attempts that actually reach the net area.

This allows analysts to better understand both possession and scoring potential.

Key Takeaways

  • Corsi includes all shot attempts
  • Fenwick excludes blocked shots
  • Corsi measures total pressure
  • Fenwick focuses on unblocked attempts
  • Using both gives better analysis

What Is Corsi in Hockey?

IHM Knowledge Center

What Is Corsi in Hockey?

How do analysts use shot attempts to estimate puck possession and overall game control?

Editor: Coach Mark • Updated: April 26, 2026

Short Answer

Corsi is a statistic that counts all shot attempts, including shots on goal, missed shots, and blocked shots. It is used as a proxy for puck possession and offensive pressure.

Full Explanation

Corsi is one of the foundational metrics in hockey analytics. It tracks every attempt to direct the puck toward the net.

This includes:

  • Shots on goal
  • Missed shots
  • Blocked shots

The idea behind Corsi is simple. Teams that control the puck more tend to generate more shot attempts over time.

Because direct possession time is difficult to track accurately, Corsi is used as a practical way to estimate which team is controlling play.

Corsi is often expressed as a percentage. If a team has 55 percent Corsi, it means they are taking more shot attempts than their opponent.

How Corsi Reflects Game Control

Corsi helps show which team is spending more time in the offensive zone and applying pressure.

Teams with strong Corsi numbers typically:

  • Control puck possession
  • Maintain offensive zone time
  • Force opponents to defend

However, Corsi does not measure shot quality. A team can have strong Corsi but still create low-danger chances.

This is why Corsi should be combined with other metrics like expected goals and high-danger chances.

NHL vs IIHF Context

Corsi is most commonly used in NHL analytics due to detailed tracking data.

In IIHF hockey, the same concept applies, but interpretation may vary depending on style of play and data availability.

The core principle remains the same across all levels.

Why Corsi Is Controversial

Corsi is controversial because it does not differentiate between dangerous and non-dangerous shots.

Fans may see a high Corsi percentage and assume dominance, but coaches understand that not all shot attempts create real scoring threats.

A team may generate many low-quality shots while the opponent focuses on fewer but better chances.

This difference creates debate about how much value Corsi should have in evaluation.

Edge Case: High Corsi but Weak Offense

A key edge case occurs when a team has strong Corsi numbers but struggles to score.

This usually happens when:

  • Most shots come from the perimeter
  • The slot is well defended
  • The goalie has clear visibility
  • There is little pre-shot movement

In this case, Corsi reflects pressure but not effective offense.

This is why combining Corsi with shot quality metrics is critical.

IHM Signal System: How to Read Corsi

To interpret Corsi correctly, focus on these signals:

  • Shot location: Are attempts coming from dangerous areas?
  • Game state: Is the team leading or trailing?
  • Shot type: Quick chances or low-danger volume?
  • Defensive structure: Is the opponent allowing outside shots?
  • Trend: Is Corsi consistent over time?

Trigger-level rule:

If a team has high Corsi but low high-danger chances, the offensive pressure is almost always inefficient.

This is one of the most important signals when using Corsi.

IHM Insight: Why Corsi Is Misunderstood

Corsi is often misunderstood because it is treated as a direct measure of dominance.

In reality, it measures volume, not quality.

Two teams can have similar Corsi numbers but very different scoring potential depending on how those shots are created.

Understanding this difference is essential for proper analysis.

Mini Q&A

What does Corsi measure?
Total shot attempts.

Is Corsi the same as possession?
No, but it is used as a proxy.

What is a good Corsi percentage?
Above 50 percent.

Does Corsi measure scoring chances?
No, only shot attempts.

Should Corsi be used alone?
No, it should be combined with other metrics.

Why This Rule Exists

Corsi exists to provide a simple way to measure puck possession and offensive pressure through shot attempts.

It allows analysts to compare teams and players even when direct possession data is not available.

Key Takeaways

  • Corsi counts all shot attempts
  • It is used as a proxy for possession
  • High Corsi means more offensive pressure
  • It does not measure shot quality
  • Context is required for proper interpretation