Youth development is a tricky thing. Creating and nurturing players in an academy is hard enough, but finding a spot for those talents in the first team is even harder. In a world with so much money, you have to be truly special to break through.
For some teams, bringing through these homegrown talents is not so challenging. Tifosy took a look at all the squads in Europe's top five leagues to see which teams have the biggest percentage of academy graduates in their current squad.
Here are the top 15 from England, Spain, Italy, France and Germany.
15. Southampton - 23.8%
For many years now, Southampton have been seen as one of England's finest academies. We've seen the likes of Gareth Bale, Adam Lallana and Theo Walcott break through at St Mary's, and the trend is still continuing.
James Ward-Prowse and Jack Stephens are among the most high-profile academy graduates in the squad, while young Michael Obafemi is expected to enjoy a lengthy career in the top flight.
14. Bayern Munich - 24.1%
Bayern Munich might have a reputation for hoovering up the Bundesliga's top stars, but they also give plenty of opportunities to their youngsters as well.
The likes of David Alaba and Thomas Müller have gone from academy stars to first-team heroes, and Bayern also have plenty of young players who are expected to follow suit.
Joshua Zirkzee has already made an impact at senior level, and Lukas Mai, Oliver Batista Meier and Christian Früchtl could all form another homegrown spine for years to come.
13. Freiburg - 25.9%
Freiburg broke their transfer record last summer when they brought Vincenzo Grifo back for around £6m. With money often fairly tight at the club, it should come as no surprise to see them rely on their academy.
Left-back Christian Günter (NOT Wales and Reading's Chris Gunter) leads the charge, but there are several youngsters who have been called up this season to add some depth.
12. Arsenal - 25.9%
Arsène Wenger's love of developing young players still remains at the Emirates Stadium today. Even though there have been plenty of expensive additions in the last few years, the path from academy to first team at Arsenal is still very clear.
Héctor Bellerin has long been the poster boy for Arsenal's academy, but with the impact of Bukayo Saka, Joe Willock, Reiss Nelson and Eddie Nketiah this season, there are a few faces for young Gunners to look up to.
11. Villarreal - 26.1%
If you're looking for a talented youngster in Spain, starting your search in Villarreal's academy is a smart move. Rodri and Paulo Fornals have gone on to leave the club, but many remain.
Their squad is full of important graduates like Gerard Moreno, Manu Trigueros and Mario Gaspar, and young stars Samu Chukwueze and Pau Torres are leading the next generation of breakthrough talents.
10. Marseille - 26.9%
Marseille always have a regular stream of players coming through the ranks. Boubacar Kamara and Maxime López are the current heroes, following in the footsteps of former graduates like Samir Nasri and André Ayew.
It's a bit early for other players like Lucas Perrin, Florian Chabrolle and Alexandre Phliponeau, but you can see how Marseille are already busy working on their future.
9. Werder Bremen - 28.1%
With a reputation for producing players for other Bundesliga teams, Werder Bremen's youth record is an intriguing one.
Losing Max Kruse last summer opened the door for a new academy poster boy at Weserstadion - a role which has since been claimed by midfielder Maximilian Eggestein.
8. Nantes - 28.1%
Nantes' position on this list is a little misleading as most of the academy graduates in the first team have barely made an impact.
Midfielder Abdoulaye Touré boasts over 100 top-flight appearances, and the closest to him is young midfielder Imran Louza, who only made his Ligue 1 debut in the final game of the 2018/19 campaign. Behind those two are plenty of youngsters who are just waiting for their chance to shine.
7. Chelsea - 29.6%
Chelsea have well and truly shaken off their reputation as a wasteland for young talent. Under Frank Lampard, the Blues have re-opened the door to the academy.
Tammy Abraham, Mason Mount, Callum Hudson-Odoi and Reece James are just four of the current group of graduates, and there are expected to be plenty of others following in the near future.
6. Köln - 31.0%
When you come through the academy at Köln, there's always a pressure to follow in Lukas Podolski's footsteps.
The latest player trying to reach that kind of level is exciting left-back Noah Katterbach, who joined veterans Mark Uth and Timo Horn in the squad last summer.
5. Hertha BSC - 31.3%
Hertha BSC helped the likes of Nico Schulz and Jérôme and Kevin-Prince Boateng break into the senior game, and there are plenty of exciting stars in the making in the current team.
Stealing the headlines are Arne Maier, Maximilian Mittelstädt and Jordan Torunarigha, all of whom have been touted as future stars of the German national team.
4. Mainz 05 - 33.3%
Germany's highest-ranking side is Mainz 05, whose number is enhanced by the presence of five youngsters who are yet to actually make an appearance for the first team.
Of the current group, there are high hopes for midfielders Ridle Baku and Erkan Eyibil, but there's still a lot of development to be done at Opel Arena.
3. Celta Vigo - 33.3%
Celta Vigo have lost academy graduates like Jonny Otto, Rodrigo Moreno and Joselu in recent years, but their squad is still full to the brim of homegrown talent.
Some of the biggest names include Liverpool legend Iago Aspas and midfielder Denis Suárez, while Santi Mina and Brais Méndez also add to the quality in the first team.
2. Athletic Club - 37.5%
Leading the charge for Spain's sides is Athletic Club, whose policy of only recruiting players from the Basque region is well-known to any player of Football Manager.
Such an intense focus on the academy has brought us players like Aymeric Laporte and Kepa Arrizabalaga, and there are still plenty of stars like Iñaki Williams, Yeray Álvarez and Yuri Berchiche knocking about.
Add the likes of Beñat, Iker Muniain and Mikel San José to that group and you'll see just how successful Athletic's cantera have been.
1. Manchester United - 40.7%
The clear leaders on this list, Manchester United's academy has a reputation like no other. The club have played over 4,000 matches since they last named a matchday squad without an academy graduate in.
This season, Ole Gunnar Solskjaer has had plenty of players to choose from. Paul Pogba, Marcus Rashford and Scott McTominay are all first-team stars, and they're accompanied by Mason Greenwood, Brandon Williams, Jesse Lingard and more.
Most teams on this list owe their position to the presence of unproven youngsters in the squad, but not United. There's a whole lot of star power coming out of the academy.
Source : 90min