By now, it is clear that the Relative Age Effect (RAE) creates an unfair advantage in football. Players born in the early months of the year dominate youth academies, receive better training, and have a much higher chance of making it as professionals. Meanwhile, late-born players—despite having the same potential—struggle to get noticed, often missing out on crucial opportunities before they have even had a chance to develop.

If football is supposed to be a game of pure talent and hard work, how can the system be fixed to ensure that birth month does not determine a player’s future?

Some clubs, national teams, and researchers have started addressing the issue, but changing a deep-rooted bias in football is not easy—especially when most people do not even realize it exists.

Belgium’s Radical Experiment: The Future Project

Belgium, despite being a relatively small country, has produced some of the world’s best footballers in recent decades—Kevin De Bruyne, Eden Hazard, Thibaut Courtois, and Romelu Lukaku, to name a few. But in the early 2000s, Belgian football was in decline. The national team was struggling, and talent development was falling behind compared to bigger footballing nations.

This led Belgian coaches to ask a simple but important question: Are we missing out on talent because of the Relative Age Effect?

Enter Bob Browaeys, the architect of Belgium’s Future Project.

Browaeys and his team realized that many potentially great players were being discarded too early simply because they were born later in the year. The traditional youth system favored bigger, early-born players, meaning smaller, late-born players never had the same opportunities to develop.

To address this, Belgium introduced a bold solution: create shadow teams made up entirely of late-born players.

These teams would mirror the main youth national teams at different age levels but would only consist of players born in the second half of the year. They would receive the same level of coaching, training, and competition, ensuring that they were not left behind simply because they developed later.

The results were overwhelmingly positive.

• Players like Thibaut Courtois (May-born) and Dries Mertens (December-born) benefited from extra patience and support instead of being overlooked.
• Belgium expanded its talent pool by keeping late-blooming players in the system rather than discarding them too soon.
• Other nations began to pay attention to Belgium’s approach, realizing that they, too, were losing late-born talents due to selection biases.

The Future Project proved that the Relative Age Effect was not just real—it was actively harming football development worldwide.

Biological Age vs. Calendar Age: A Fairer Way to Group Players?

One of the most radical ideas for fixing the Relative Age Effect is changing how youth players are grouped.

Right now, players are categorized by calendar year, meaning a January-born child competes in the same category as a December-born child, despite being almost a full year older. But what if players were grouped based on biological age instead?

Biological age classification would take into account:

• Physical development, such as height, muscle mass, and coordination.
• Mental and emotional maturity.
• Growth rate predictions.

This approach would allow players to compete against others at a similar stage of development, rather than just those who happen to be born in the same year.

Some countries, including Italy and Ireland, have started experimenting with biological age assessments, measuring growth patterns instead of relying solely on birth certificates. While this method is not perfect, it could help level the playing field and give late-born players a fairer chance.

Adjusting Selection Processes in Academies

Football scouts and academy coaches tend to look for the best players at a given moment, rather than those with the most long-term potential. As a result, early-born players—who are bigger and stronger at a young age—stand out more and get picked, while late-born players often go unnoticed.

Some clubs are now taking steps to recognize and adjust for this bias.

• Ajax, Barcelona, and Bayern Munich have introduced policies to track birth month trends in their youth academies, ensuring that they are not unintentionally favoring early-born players.
• English clubs have begun delaying final academy selections until later in a player’s development, giving late-born kids more time to catch up.
• Data analysts in scouting are starting to compare players based on their age relative to their physical development, rather than just raw ability.

By changing the way young players are selected and developed, clubs can avoid making short-sighted decisions that overlook future stars.

The Reality: Why It Is Hard to Change the System

Despite these promising efforts, the Relative Age Effect remains a major problem in football, and fixing it is not as simple as changing a few rules.

There are several reasons for this:

• People trust what they can see. Coaches, scouts, and fans naturally gravitate toward bigger, stronger players, even if those players only seem better because they are older.
• Football is a results-driven business. Youth coaches are under pressure to win games, not just develop talent. This makes them more likely to choose early-born players who can help them win immediately, rather than late-born players who might develop into stars later.
• Change requires time, money, and education. Adjusting youth development programs means retraining scouts, changing academy structures, and investing in long-term research. Many clubs and federations do not see this as a priority.

In other words, while the solutions exist, they require football culture to evolve—and that takes time.

In Conclusion

The Relative Age Effect has shaped the careers of countless footballers, giving some an unfair advantage while making life much harder for others. But as research continues to expose these biases, football is slowly finding ways to level the playing field.

From Belgium’s Future Project to the idea of biological age classification, efforts are being made to ensure that talent is not lost simply because of birth month. However, overcoming deeply ingrained traditions in football will not happen overnight.

So, is there still hope for late-born players to succeed in today’s system? And what happens to those who manage to beat the odds despite all the challenges?

That is what we will explore in Part 5.

Sources

Outliers Full Book Summary
Do Guys Keep Growing Until Age 25?
Relative Age Effect Among the Best Norwegian Track and Field Athletes of All Time: Comparisons of Explosive and Endurance Events
Relative Age Effect
How important is the birth date in football players’ sports career?
Malcolm Gladwell: Full Exclusive Interview - No Small Endeavor
Are European Soccer Players Worth More If They Are Born Early in the Year? Relative Age Effect on Player Market Value
Birth Advantages in Male Italian Soccer: How They Influence Players Youth Career and Their Future Career Status
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How a footballer’s birth month can affect their chances of reaching the top
Study reveals birth month impact on soccer careers
Relative age effect:a serious problem in football
The relative age effect is larger in Italian soccer top-level youth categories and smaller in Serie A
Matthew Effect | Definition & Application
Belgium are much more than a golden generation and it is not luck
The curious tale of the football international nobody ever heard of (because he was born in the wrong month)
“Is early reliable TID possible? No. Is it necessary? No, it is not.” - Prof Dr Arne Güllich