Football analytics and the use of data has transformed the way that top European clubs select players. Clubs dont only apply these metrics to players they buy from other clubs, but also use them to evaluate players within their own academy systems.
Today, many clubs utilize advanced data collection methods like fitness trackers and fit-bits. They also pay big money to have people analyse the results and create metrics they can follow to identify top measurements for players.
Even youth and amateur teams are using KPIs (Key Performance Indicators) to measure the relative efficiency of their defense and attack. Many coaches share this data with players to encourage improved performance and a spirit of healthy competition. They will often also be combined with video analysis of games, highlighting examples of good play but also mistakes with the intention of learning from them.
Analysts have been able to demonstrate that football, despite its reliance on passion and its tendency for randomness, has constant patterns and predictable patterns which can be mapped and exploited.
Some measurements are considered more indicative of future success than others, and as such are regarded as having greater relevance and providing a more accurate indicator of future performance.
One of the key metrics for any young players is possession, which can be measured in various ways but, essentially boils down to one key message how often does a player get the ball, and how often do they give it away?
At the top level, ball retention is a key skill the ability to receive the ball, keep it under pressure and then pass it on to the next player or get a shot away.
Distance covered is also an important metric. The physical demands of the game have increased substantially in recent years, with players covering between 4 6 km more during the average match than they did two decades ago. Stamina is key because teams need to know that young players will be allowed to last 90 minutes plus (taking in injury time and occasionally extra time in cup competitions) and not need to be substituted with 20 minutes to go.
And, unlike sports like athletics where the pace is continuous, a footballer will make lots of short sprints, interspersed with short periods of rest. Data helps identify those with the ability to withstand the physical demands of the sport at the highest level.
Pass completion is also a key metric how often do passes, short or long, find a teammate? Again, it is easy to see why. Football is a low scoring game and usually depends on having the ball in the first place in order to put the ball in the net.
There are also a number of position specific metrics that are used XG (Expected Goals) for strikers tackles won for midfielders and defenders, shots faced and saved for goalkeepers for example.
Scouts used to claim that they had a gut feeling when they spotted a good young player. However, for every hit, in reality there were ten misses with such an approach.
The reality is that only 180 of the 1.5 million players in organized English youth football will make it as a Premier League professional. Given those odds and the vast sums of money top European clubs are pouring into their academies now, they have neither the time, nor inclination or money, to trust on instinct alone any longer.