Not all goals have the same weight, and not all occasions are the same: the Expected Goals (XG), Or “expected goals”, are born to answer an apparently simple question, but fundamental in modern football: how many goals a team would have had to really score, regardless of the final result? In practice, XG are an advanced statistics that measures the probability that a shot will turn into scoringbased above all on the quality of the occasions created or granted. To calculate them, thousands of shots are analyzed considering factors such as the distance from the goalkeeper, the shooting angle, the position of the defenders, the part of the body used and the type of passage that led to the action. What is all this for? The XG offer a powerful tool to analyze the game on several levels: they allow you to understand how a team builds its occasions, evaluate the ability of a player to create or exploit the opportunities, and even estimate how much luck or unfortunate has influenced the result, comparing the real goals with those “expected” by the models.
What is the Expected Goal (XG) and what it means shortly
The Expected Goals (XG) Or “expected goals” are a statistical data that measures the probability that a shot will become goals. To get to that number you do not look at chance, but thousands of shots are analyzed: an inclusive value is assigned to each conclusion between 0 and 1Where 0 means “Impossible to score”While 1 is equivalent to “Practically certain goals”.
The calculation, however, is not always identical. In fact, there are several models, some more complex than others, which take into account various factors such as the Distance from the door, the shooting angle, the position of the defenders, the part of the body used (foot, head, etc.) or the type of assist which led to the conclusion. In this way, shots made in similar conditions can be grouped and evaluated according to their “average difficulty”.
And it does not end here: by adding the XG of a team in a game you get an immediate idea of his offensive danger. If, for example, a team collects 2.5 XG But he only scores one goal, it means that he probably wasted a lot (Underperformance); On the contrary, if it scores 3 goals with 1 xgmeans that it went beyond expectations (Overperformance).
How to calculate the XG and what it is for
Let’s start with the simplest definition: Expected Goals measure the danger of a team or a player under the net. So far, nothing particularly complicated. The difference comes when trying to understand how, really, is calculated An XG in a game. The calculation of the XG is based on a statistical modelconstantly updating, built by analyzing hundreds of thousands of shots. As we said, each conclusion towards the door is transformed into a probability of realization that goes from 0 to 1but be careful, it is not an opinion, but a rigorous mathematical model.
For example, if a certain point of the field have been kicked 500 shots and only 50 found the networkthe probability of marking from that position is of 10%so the XG will be 0.1. Likewise, a shot practically on the door line can reach 0.99 xg: Almost certain, but never completely guaranteed, because the statistics take into account all the times in which even from positions very close to the goal, a shot has not been concretized.
There is no single XG model: the calculation can vary depending on the parameters and algorithms used by different platforms of football analysis. Among the most relevant factors there are the position on the pitch of the shooter, the part of the body used to kick, the type of action (maneuvered action, counterattack, inactive ball) and, for the penaltiesan almost fixed XG, which varies between 0.76 and 0.79.
To the XG is added another advanced statistics, the Expected Assists (XA)which measure the ability of a player to serve companions in favor of shooting, and goalkeepers metrics, which evaluate how effectively an extreme defender neutralizes the opposing occasions.
Concrete examples of matches or seasons to better understand the concept
One of the most interesting aspects of XG and gods expected points (XPTS) – Another advanced statistics – emerges when we compare the theoretical data with the real ones of the season. For example, Napoli closed the series A 2024/2025 with 82 Royal Pointsbut the model of XPTS he attributes about him 71 points. This means that, according to the quality of the occasions created and granted, Napoli has overperor: He transformed some games into victories in which, on paper, he should have obtained less points. Inter, second classified, shows a similar but more “contained” story: 81 real points against 75 of XPTS. Here is the overperperformance, but less evident.
Widening the gaze, surprising stories such as the one that concerns the last classified, the Monzawhich closed last season with only 18 pointsbut his XPTS was about 31. The Brianzola team also has underperperformed from the point of view of the goals scored, with 28 Goal marked at the expense of an XG of 32. The data concerning the Romearrived fifth in the standings, she suffered 35 total goals to the detriment of a XG of 48granting much less than we would have expected from the occasions created by the opponents.
Always in the slums of the Serie A ranking of the past season we find theEmpoliarrived 18th and relegated to Serie B. If we look at the royal points of the Tuscan team, we see that the team has closed the season with 31 pointsbut the XPTS They say a completely different story: 41 points. This means that, on paper, based on the occasions created and granted, Empoli should have collected almost 11 more points.
Citing some matches of the past season, we find some very surprising data. For example, Hellas Verona-Napoli of 18 August 2024 saw the home team triumph 3-0but the data on the XG show a data of Hellas 1.81obvious sign that he has overperformed while for the Neapolitans they show 0.81.
Another game of the Serie A 2024/2025 that deserves attention from the point of view of the Expected Goals is Juventus-Inter over 1-0 In favor of the bianconeri of February 16, 2025. This match highlighted a clear discrepancy between the real result and statistical expectations. But here too the XG tell a completely different story. Juve has scored 1.37 XGwhile Inter even 2.09 xg. Translated: the Nerazzurri would have had to score more goals, create more dangers and, in theory, take the victory home.
