Thibaut Courtois vs Marc Andre ter Stegen Save Difficulty and PSxG Calculator

The Thibaut Courtois vs Marc Andre ter Stegen Save Difficulty and PSxG Calculator compares save difficulty and post-shot expected goals for both goalkeepers from input shot data.

What Is a Thibaut Courtois vs Marc Andre ter Stegen Save Difficulty and PSxG Calculator?

This calculator estimates how hard the shots were that each goalkeeper faced and how many goals they prevented relative to expectation. It relies on post-shot expected goals, often called PSxG or xG on target. That metric evaluates the chance that a specific shot on target becomes a goal after it leaves the shooter’s foot or head.

Unlike simple save percentage, PSxG considers where the ball was placed, its speed, the angle, deflections, and surface type. Save difficulty expresses the average danger level of the shots a keeper faces. Comparing Thibaut Courtois and Marc Andre ter Stegen with these measures helps you judge shot-stopping independent of team defense strength.

You can apply it to a single match, a run of games, or a full season. The output highlights expected save percentage, actual save percentage, and goals prevented. That gives a direct, intuitive read on performance.

Equations Used by the Thibaut Courtois vs Marc Andre ter Stegen Save Difficulty and PSxG Calculator

The calculator uses a simple framework that mirrors common analytics practice. It starts with shot-level PSxG, aggregates by keeper, and converts the totals into friendly summary stats.

• Shot-level PSxG model: PSxG_shot = logistic(b0 + b1·distance + b2·angle + b3·body_part + b4·shot_speed + b5·deflection + b6·placement + …).
• Save difficulty (per shot on target): SD = average(PSxG_shot) for all shots on target a keeper faces.
• Expected save percentage: ExpSV% = 1 − SD.
• Goals prevented: GP = sum(PSxG on target faced) − goals conceded.
• Rate stat for comparison: GP per 90 = GP ÷ minutes × 90; you may also use SD × 100 for a percent feel.

These formulas do not replace provider-grade models. They provide a transparent, coach-friendly summary. The key insight is that a higher average PSxG per shot means tougher chances faced, while a positive goals prevented value means the keeper outperformed expectation.

The Mechanics Behind Thibaut Courtois vs Marc Andre ter Stegen Save Difficulty and PSxG

PSxG evaluates shots after ball contact, so it captures ball placement and speed that traditional xG misses. Save difficulty counts how many of those dangerous shots a keeper faced on average. This lets you separate defensive structure from pure shot-stopping.

• Shot context: distance, angle, and body part set the base probability.
• Post-shot features: ball speed, trajectory, placement within the frame, and deflections adjust the chance.
• Keeper task: expected save percentage drops as average shot danger rises.
• Aggregation: summing PSxG across shots produces an expected goals conceded total.
• Performance delta: goals prevented is the gap between expected and actual goals conceded.

Courtois and Marc Andre ter Stegen often face different shot profiles due to tactics and league styles. A tougher schedule or a high line can raise save difficulty. That is why you should compare both raw goals prevented and the difficulty-adjusted rates.

Inputs, Assumptions & Parameters

Set the scope first. Choose a match, month, half-season, or full season. Then enter the core counts and the PSxG totals for each goalkeeper.

• Shots on target faced (SoT) for Courtois and for Marc Andre ter Stegen.
• Goals conceded (GA) for each keeper within the same sample.
• Sum of PSxG on target faced (PSxGOT) for each keeper.
• Minutes played for each keeper to normalize per 90 metrics.
• Penalties: separate counts for penalties faced, goals, and PSxG from penalties.
• Model version: note the provider or coefficients used to compute PSxG.

Keep inputs on the same scope for both keepers. If your PSxG source includes penalties, consider reporting penalty-only splits, since penalties have very high PSxG. Use realistic ranges: SoT from 0–400 per season, GA from 0–100, PSxGOT from 0–60. If SoT is zero, skip save percentage and use rate stats once you have data.

How to Use the Thibaut Courtois vs Marc Andre ter Stegen Save Difficulty and PSxG Calculator (Steps)

Here’s a concise overview before we dive into the key points:

1. Select the time window and competitions to compare.
2. Enter SoT, GA, PSxGOT, and minutes for Courtois.
3. Enter SoT, GA, PSxGOT, and minutes for Marc Andre ter Stegen.
4. Choose whether to include penalties or report them separately.
5. Compute average PSxG per shot, expected save percentage, and goals prevented for each keeper.
6. Compare the outputs and note who faced tougher shots and who saved above expectation.

These points provide quick orientation—use them alongside the full explanations in this page.

Example Scenarios

Case 1: League stretch of 10 matches. Courtois faced 50 shots on target, conceded 12, and the PSxGOT total was 15.0. His save difficulty is 15.0 ÷ 50 = 0.30. His expected save percentage is 1 − 0.30 = 70%. His goals prevented is 15.0 − 12 = +3.0. He saved three more goals than expected against an average shot danger of 0.30. What this means

Case 2: Same stretch for Marc Andre ter Stegen. He faced 45 shots on target, conceded 11, and the PSxGOT total was 12.6. His save difficulty is 12.6 ÷ 45 ≈ 0.28. His expected save percentage is 72%. His goals prevented is 12.6 − 11 = +1.6. He saved above expectation but faced slightly easier shots than Courtois. What this means

Accuracy & Limitations

PSxG is a model-based estimate, not a fact. Different vendors build different models, and camera-tracking precision varies. Results depend on sample size, opponent mix, and whether penalties are included.

• Provider differences: StatsBomb, Opta, and FBref may report different PSxG values.
• Sample size: short runs swing widely; use per 90 and confidence bands if possible.
• Context gaps: walls, screens, and late ball movement are not always captured.
• Team effects: pressure on shooters and blocking lanes can change shot quality.
• Data quality: mislabeling deflections or speeds skews PSxG.

Treat goals prevented as directional evidence, not a verdict. Track trends over time, compare splits home and away, and sanity-check against video.

Units and Symbols

Units make your numbers comparable. Probabilities sit between 0 and 1. Rates should use minutes to standardize. Keep penalties separate because their baseline probability is high.

Read the table left to right. Start with per-shot PSxG. Aggregate to PSxGOT, divide by SoT to get difficulty, and net out goals to get goals prevented.

Tips If Results Look Off

If your outcomes seem strange, check the inputs and the scope. Small misalignments can change the story a lot.

• Confirm that SoT, GA, and PSxGOT cover the same matches.
• Separate penalties, own goals, and deflected shots if your model handles them differently.
• Check minutes; per 90 rates need accurate playing time.
• Verify PSxG source and version; do not mix providers without noting it.

When in doubt, re-run the sample over a longer window. Then compare home and away splits to see if context drives the shift.

FAQ about Thibaut Courtois vs Marc Andre ter Stegen Save Difficulty and PSxG Calculator

Does a higher save difficulty mean better goalkeeping?

No. Save difficulty measures the average danger of shots faced. To rate goalkeeping, combine save difficulty with goals prevented or save percentage above expected.

Why can goals prevented be negative for a top keeper?

Even elite keepers have down stretches or face lots of low-PSxG shots. Conceding more than expected in that window produces a negative value.

Should I include penalties in PSxG?

Report them separately. Penalties have a high baseline and can dominate totals. Comparing keepers without a penalty split can mislead.

Can I use this for single matches?

Yes, but variance is huge. Use match results for storytelling, and rely on 8–10 game windows or full seasons for stronger conclusions.

Key Terms in Thibaut Courtois vs Marc Andre ter Stegen Save Difficulty and PSxG

Post-Shot Expected Goals (PSxG)

A probability that a specific on-target shot becomes a goal, based on ball placement, speed, angle, and other post-shot features.

Save Difficulty

The average PSxG per shot on target faced by a keeper. Higher means tougher shots on average.

Goals Prevented

The difference between expected goals conceded from PSxG and actual goals conceded. Positive values indicate above-expectation shot-stopping.

Expected Save Percentage

One minus save difficulty. It is the save rate you would expect against the average shot profile faced.

Shots on Target (SoT)

All shots that require a save or result directly in a goal. Headers and footed shots both count if they are on target.

xG on Target (xGOT)

A common label for PSxG totals. It aggregates post-shot goal probabilities across shots on target.

Per 90

A rate statistic scaled to a 90-minute match. It helps compare keepers who played different minutes.

Model Version

The specific PSxG model and coefficients used. Different providers produce different values from the same shots.

Sources & Further Reading

Here’s a concise overview before we dive into the key points:

• StatsBomb: Introducing Post-Shot xG
• The Athletic: Expected goals explained, including xGOT
• FBref: Expected goals model and glossary
• Opta: What is expected goals?
• Soccermatics: Shot models and logistic regression overview

These points provide quick orientation—use them alongside the full explanations in this page.