Building a successful squad is all about finding the right balance of technical abilities, physical attributes and temperaments.
This is often true for the age profile of a team too, as managers look to find the perfect blend of youth and experience.
Young players can have a fearless exuberance that older players lack, but might not perform to the same level as consistently.
Some of the brightest stars of Euro 2024 have been at either end of the age spectrum, from teenage prospects to retirement-defying stalwarts.
You have 8 minutes to name the 20 youngest and the 20 oldest players at the Euros.
Remember to tweet your scores @FourFourTwo and share this with your mates. How many can you name overall? On your marks, get set, go!
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