The sale of academy graduates has become a hot topic in recent months, with Premier League teams offloading fringe players in a bid to raise funds for first-team investment. The increasing importance of staying with profitability and sustainability rules has forced even the richest to work smarter.
The benefit of selling academy players is that they essentially cost nothing and so any fee brought in is seen as pure profit when it comes to club accounts. And as tedious as that may sound, it is why the likes of Chelsea and Manchester City have been able to spend big in recent months.
Manchester United have raised plenty of money through such sales in recent years, moving on the likes of Anthony Elanga, Dean Henderson and Zidane Iqbal. But how do they rank among Europe's most productive and profitable academies? Take a look below.
1. Benfica - £440m
The £113m sale of Joao Felix to Atletico Madrid in 2019 was one of several high-profile outgoings. Ruben Dias for Manchester City for around £65m in 2020.
2. Ajax - £321m
Ajax made a fortune from their 2018/2019 squad, selling the likes of Frenkie de Jong, Donny van de Beek, Hakim Ziyech and Matthijs de Ligt for big money.
3. Lyon - £316m
PSG signed Bradley Barcola for around £40m last summer, the most recent from a steady stream of academy graduates that include Karim Benzema, Anthony Martial and Samuel Umtiti.
4. Real Madrid - £311m
Alvaro Morata, Achraf Hakimi, Sergio Reguilon and Marcos Llorente are four of many academy exits to have enjoyed success elsewhere.