Age of players

Someone knows if age of players really matters or just quality?
As an example we usually see coaches talking about the importance of mixing "experience" and "youth" to a good team.
May it have some influence on T11?
I meant if you have same quality and a lot of younger players, might use some experienced ones to balance
team?

It only has influence on their training speed

During a match doesn't matter if they all 18 for example? Or need some aged ones to give "experience" to team?

As far as I know, age doesn't affect player performance.

thanks dv8r!!!!