The main question we set forth to answer was the following: which goalkeepers have outperformed expectations, which goalkeepers have just about met expectations, and which goalkeepers have underperformed during the current season up to the fifteenth round.
To reach our conclusions, we looked at the fairly simple premise of goals conceded versus the number of goals each goalkeeper was expected to concede. The latter metric is called ‘expected goals against‘ and signified by the value of ‘xGA‘.
First things first, let us look at each column across the board. Which goalkeepers have conceded the most goals?
Kleyman (Enosis), Gremsl (Doxa), Rudko (Pafos), Toño (AEK Larnaca), and Bogatinov (Ethnicos Achnas) have the misfortune of leading this table. They have conceded 27, 26, 19, 19, 19 goals respectively. However, does this mean that they are most underperforming goalkeepers in the league this season? Let’s investigate further by checking expected goals against (xGA).
In terms of expected goals against, which is the number of goals a team is expected to concede depending on the quality of chances they have allowed their opponents to create, we can see the story taking a bit more shape. The goalkeepers with the highest xGA value are Kleyman (Enosis), Gremsl (Doxa), Vózinha (AEL), Bogatinov (Ethnicos Achnas), and Toño (AEK Larnaca). Their xGA is 24.75, 23.02, 18.07, 17.71, and 17.07 goals respectively. You can see where this is going.
Now, if we use both datasets, we have a clearer picture as to the individual contribution each goalkeeper makes to a team’s defensive prowess. The table that we’ve created is very simple to read but quite telling indeed. You can see which goalkeeper underperforms, overperforms, or just on par with expectations.
From the above table we can now contextualize the first metric, total goals conceded, in a much more accurate way. For example, Klayman has conceded a whopping 27 goals. However, that’s just 2.25 goals more than he was expected to concede. So, while he is underperforming, it’s not as drastically bad as initially thought.
On the other side of the chart, we can see the clear overperformers this season: Uzoho (Omonoia), Fabiano (Omonoia), Mall (Apollon Limassol), Vozinha (AEL Limassol), and Loria (Anorthosis Famagusta).
One thing that stands out here is that Omonoia Nicosia have the top two overperforming goalkeepers in the league. Of course, it must be noted that for this to have happened, Uzoho had to get injured and limited to 5 appearances this season.
Further, another thing that this tells us, is that while both keepers have done well to exceed their expected goals against figure (xGA), it also spells a troubling tale for Omonoia’s defensive organization.
The fact that they have the two most overperforming goalkeepers in the league means that their true defensive performance is masked by the man (or men in this case) between the sticks. They are systematically allowing high-quality opportunities to be created against them, meaning that when Loria eventually regresses to the mean (this tends to happen sooner or later), they might begin conceding more goals than they have so far.