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Wins tell you which goalie got the most run support. Save percentage tells you part of the story. GSAA tells you who actually stopped more pucks than they should have. Here's how the key goaltending metrics work and what they actually reveal.
TL;DR
GSAA (Goals Saved Above Average) measures how many goals a goalie saved compared to what a league-average goalie would have saved on the same shots. Positive GSAA means above average, negative means below. It's the single best traditional stat for evaluating goaltenders because it accounts for workload, unlike raw save percentage or wins.
The percentage of shots a goalie stops. League average hovers around .908. Above .915 is good. Above .925 is elite. Simple and widely used, but it treats every shot the same regardless of difficulty.
Benchmark: .925+ elite, .915+ above avg
The average number of goals allowed per 60 minutes of play. A lower GAA is better, but this stat is heavily influenced by team defense. A goalie behind a strong blue line will post a better GAA than one getting shelled every night.
Context: team defense matters more than you think
Goals Saved Above Average. Compares a goalie's save percentage to the league average, scaled by shots faced. A GSAA of +18 means that goalie saved 18 more goals than an average netminder would have on the same workload. The best single number for goalie evaluation.
The key metric: adjusts for shot volume
A quality start is any game where the goalie posts a save percentage above .885. It measures consistency rather than peak performance. A goalie with 70%+ quality starts is giving their team a chance to win most nights.
Consistency check: how often they show up
Save percentage has a blind spot: it ignores workload. A goalie who faces 25 shots per game and one who faces 35 can post the same SV%, but the high-volume goalie is doing more work and saving more goals. GSAA fixes this by scaling for shots faced.
GSAA = (.920 - .908) x 1,800 = +21.6. Facing heavy volume and stopping pucks at a high rate. This goalie is carrying their team. The GSAA reflects that impact in a way SV% alone cannot.
GSAA = (.920 - .908) x 1,200 = +14.4. Same save percentage, but fewer shots means fewer goals saved above average. Still good, but Goalie A had a bigger impact. SV% says they're equal. GSAA shows the difference.
Goaltending is one of the biggest swing factors in any NHL game. A hot goalie can steal a win against a better team, and a cold one can sink a favorite. The prediction model treats goaltending as a core input, not an afterthought.
Rather than relying on season-long save percentage, the model looks at recent form and trends to capture how a goalie is playing right now. That recency weighting is critical because goalie performance is streaky by nature.
Goaltending in the model
A GSAA above zero means a goalie is saving more goals than an average netminder would on the same shots. Elite goalies typically post a GSAA of +15 to +25 over a full season. Anything above +10 is solidly above average. Negative GSAA means the goalie is letting in more than expected, which often signals a problem regardless of what the win column says.
GSAA compares a goalie's actual save percentage to the league-average save percentage, then multiplies by the number of shots faced. The formula: GSAA = (Goalie SV% - League Avg SV%) x Shots Faced. If the league average SV% is .908 and a goalie has a .920 SV% on 1,500 shots, their GSAA is (.920 - .908) x 1,500 = +18. That means they saved 18 more goals than an average goalie would have on those same shots.
GSAA uses league-average save percentage as its baseline, treating all shots equally. GSAx (Goals Saved Above Expected) uses an expected goals model that accounts for shot quality, location, and danger level. GSAx is more precise because it adjusts for the difficulty of each shot. A goalie facing mostly low-danger perimeter shots should save more of them, and GSAx accounts for that. GSAA does not.
No. Save percentage treats every shot the same, whether it's a breakaway or a harmless wrister from the point. A goalie on a strong defensive team faces fewer high-danger chances, which inflates their SV%. A goalie behind a porous defense might post a lower SV% despite making harder saves more often. That's why metrics like GSAA and GSAx exist: they add context that raw SV% misses.