#7 Diego Simeone
League minutes played by U-23 players: 19.8%
After learning his trade in Argentina and Italy, Diego Simeone took charge of Atletico Madrid in 2011. It would be a historic appointment for the Rojiblancos who would go on to break the Real-Barca duopoly in La Liga and also finish runners-up in the Champions League not once but twice.
Once upon a time, Atletico had decided to shut their academy - a move that saw Raul slip through their fingers as he joined rivals Real Madrid. They took their time to re-establish the youth system but once they did they started to generate a number of players who would go on to wear the club's shirt.
In the 2013/14 title-winning season, two of their most crucial members were U-23 players; goalkeeper Thibaut Courtois (who used that season to announce himself to the world) and Koke (6 goals and 13 assists in 36 appearances).
Since then, Simeone has used other youngsters such as defenders Jose Gimenez and Lucas Hernandez, midfielders Saul Niguez and Thomas Partey, wingers Yannick Carrasco and Angel Correa.