Graham Potter’s Brighton and the xG (or “expected goals”) theory

The world of football is constantly changing and evolving and the rise of statistics and analytics as a whole is a very big factor in this particular situation. More and more often we see football clubs using analytics in their coaching methods and the way they structure their squads, with expected goals being a key factor in this particular situation. One of the most useful teams to explain this is Graham Potter’s Brighton & Hove Albion.

Expected goals are a very interesting aspect of football analytics and one that has become a very ordinary topic for discussion in recent years. “Expected goals” are basically statistics which suppose to calculate the chances of scoring that a team has during a game and the amount of goals they should have scored in that particular game. Quality of chances are also taken into consideration. A striker missing a shot on a one-on-one with a goalkeeper is a high quality chance. A full-back shooting from midfield and the keeper making a save is a low quality chance because the former had very little possibilities of scoring from that position. That way you can measure the amount of chances your team is creating on a regular basis and the quality of said chances.

A great example of this is the English Premier League team Brighton & Hove Albion because they are one of the most attacking teams in the league, but they tend to struggle meeting the expectations set by their xG, as expected goals are commonly known. In short: they create a lot of good chances, but they fail to score. This is mostly down to the quality of their strikers or simply bad luck. But the reason xG has become so popular is that it has a clear message: even if you are not scoring your chances, you are creating them. As a result, you need a better finisher to capitalize those chances.

A great example of this was the recent game of Brighton against Tottenham. Brighton have failed to meet their xG for most of the season while Tottenham, mostly through the sheer brilliance and great form of Harry Kane and Son, have exceeded their xG. In this particular situation, the results were actually the opposite: Brighton, with an xG of 1.97, beat Tottenham, who had an xG of 0.46, by a 1-0 score, which is mostly faithful to what the numbers are telling us.

Does this mean expected goals can be viewed as gospel? Of course not. Football is filled with uncertainty and statistics exist to be defied, but it can be a very interesting element of the game, especially with a team like Brighton that plays a very appealing brand of football.