A familiar concept by now. This metric incorporates what is commonly known as post-shot xG, usually shortened as xG² or xGC (expected goals conceded) — the younger of two xG methods that only considers shots on target (ie. shots that can actually turn into goals) and accounts for stuff like shot power and shot placement (ie. stuff the traditional xG method typically doesn’t consider). This post-shot xG then gets turned into the so-called “prevented goals” metric that follows the simple equation of expected goals conceded-minus-conceded goals, divided by the number of starts (to get a 90-minute average). Crucially, diverging from the catch-all Wyscout method, I’m not including penalties and don’t count own goals among goals conceded, giving the stat a fresh look that truly reflects one’s shot-stopping (whereas earlier it played in randomness’ favour more).

This builds on the previous one in that it's based on expected goals conceded (xGC), but does include penalty saves for the benefit of the goalkeeper. Any shot that would — per xGC — result in a goal scored in at least 40% of cases (ie. value of 0.4+ xGC) is credited to the custodian as a high-danger save. As ever with arbitrary cut-offs, you could easily argue there’s no difference between 0.39 and 0.41 shots (and you’d be right) but we need an objective framework to complement our fundamentally subjective view of football and we wouldn’t be gaining anything by allowing for tolerance (a 0.02 xGC difference would be negligible at any point of the scale, so we'd be entering a deep rabbit hole either way). The shots warranting at least the 0.4 xGC value typically fall into the following categories: A. close-range stunner, B. mid-range diving save, or C. well-placed one-on-one. Disclaimer: Anecdotally speaking, the latter category is not as bloated as one would expect, since a botched one-on-one often includes a shot right into the goalkeeper's chest, rarely deserving a high value. This way, the shooter isn't credited with a quality finish - see the expected goals scored metric for centre forwards - and that is how it should be. However, to reward goalkeeper's positioning (often to blame for a one-on-one that indeed appears botched from a shooter's perspective), I track memorable one-on-one saves and dish out bonus points for them.

My very own semi-scientific approach to the age-old “he doesn’t save anything extra” complaint about a mediocre goalkeeper — simply taking all 0,4+ xGC shots faced to see the proportion of goals actually conceded. Anyone who scores high in this metric should have no trouble avoiding the common complaint. Here, penalties are not considered for neither the trouble nor the benefit of the goalkeeper in question. While the high-danger saves metric (normalized per game) often boils down to opportunity, this one is a good complement where even a Slavia goalkeeper can rank high, as highlighted by Aleš Mandous appearing below average in hdSV/90 but comfortably elite (top 5) in hdSV%. Similar case: Jindřich Staněk in 22/23.

Here I take a look at what’s the average xGC value of any non-penalty shot the particular goalkeeper faced across the season, and compare it against the average xGC value of all non-penalty attemps the said goalkeeper allowed to fly past him. With not a single exception in my time doing this, regular goalkeepers with 10+ starts always allow goals of far higher average value than the usual shot (there’s always a bunch of easily saved long-range hopefuls bringing the overall average down), but the important question is how much higher. And it’s not like we’d be splitting hair, with the difference ranging from 0.17 to 0.31 last season, and from 0.14 to 0.36 this season (24/25). Last campaign was the first one with a pizza chart featuring this quirky metric, and 3/4s of the Top 4 easily stand the eye test: Antonín Kinský, Adam Zadražil and Jiří Letáček. Let's not speak of © The Outlier.

Anytime I use the term "stole" or "botched" a game, it has a scientific backing alright! In effect, it means the goalkeeper in question either saved (stole) or allowed (botched) a certain amount of expected goals conceded above (stole) or below (botched) reasonable expectation. Here, penalties and own goals come into consideration as opposed to the prevented goals metric, since it wouldn't feel right otherwise. The threshold for stolen/botched game is at plus or minus 0.81 xGC, ie. the value of one penalty kick. Don't ask me why I chose this inspiration in particular.

Once again I take every single one of the goalkeeper's performances at face value (inclusive of penalties, own goals) and simply compare the number of times he fits into the Top 100 of goalkeeping performances (in terms of prevented goals) over the whole campaign, cut shorter by the number of times he conversely fits into the Worst 100 of goalkeeping performances. Just a bit of fun.

This one is obviously another xGC-based metric, but it falls into a different category simply because it speaks less to one's reflexes, and more to one's attention span. Otherwise it's exactly what it says on the tin: I consider exclusively the mid/long-range shots and do the classic xGC-GC.

This is an interesting metric in that it accounts for both misplaced passes but also lost aerial or ground duels. The follow-up shot needs to occur inside the next 20 seconds per Wyscout rules, otherwise it’s rendered a “harmless” loss, which is yet another case of an arbitrary cut-off you can argue against, but it's about everything you can do about it. My bigger problem with this metric is: what if the loss is truly staggering and awful, yet the opposition is even worse and passes its way to a corner flag instead of shooting? Let’s assume it’s down to the goalkeeper’s psychic powers (and also we'll account for those shot-less cases further down the line, no worries).

This is where my subjective view comes to play for the first and decidedly not the last time, but since it’s me and only myself considering things all the time (with my lens that could be challenged but at least remain fairly consistent), I’d argue the subjectivity doesn’t cause too much actual harm. As for what it means: simply how big a portion of goals conceded I deemed to be the goalkeeper’s fault. And by fault I mean blatantly so. For example, I’m not setting the goalkeeper back for any seemingly flawed positioning on a shot, as I’m not the expert. But if he’s caught off position due to miscommunication with his defender? Oh he’s absolutely tagged. When he’s clearly slow to react, allows an easy tap-in unnecessarily, or sets up an empty-netter with a poorly timed rush off the line or misplaced pass, then he’s quite clearly at fault, as well. Previously, I also had a metric called “grave errors leading to goal” to double down on this, but since there’s always a few with 0, it didn’t make much sense to me anymore, plus the line between grave error and just any error was always a bit blurry. Now it's just a garden variety of errors divided by all non-penalty goals conceded, simple as.

I have dabbled with this kind of a thing before, but I always went about it the wrong way until settling on this version of a consistency metric for 23/24. Previously, I wanted to see overperformance rather than underpeformance, which inevitably disadvantaged those who didn’t face a single shot on occasion (when they had literally nothing to overperform and looked worse for it, an everyday worry of a Slavia goalkeeper nowadays). Now, I only consider full starts (no subs in or off) and compare the ratios of below-par (below zero) performances per prevented goals metric. I also briefly considered noting the so-called hot and cold streaks — strings of positive or negative performances, considering their respective extreme lengths, but since there would once again be little variety, I’m leaving it off the visuals entirely, with the odd mention in the text here and there.

Since I take note of all shots a goalkeeper faces across the season, I can easily pull the individual's hottest and coldest runs from my spreadsheet, specifically in terms of the most saves made in a row for the hot kind, and the most consecutive shots let past without making a single stop inbetween for the cold kind. Due to some spreadsheet functionality limits, a penalty save/goal always means a do-over for the count, but I'll make sure to note in the text if such a rare occurrence disturbs an otherwise particularly long hot/cold streak, no worries. It's hardly ever the case.