Sunderland are hoping to use their development squads more effectively in the future.
Advocaat has recently taken charge of Sunderland and he wants to offer his back-up players a more regular chance to play for the side's Under-21 team.
The Black Cats boss feels that by playing members of his squad who haven't received much first-team action for the development side he can keep the entire squad's fitness levels up.
At present clubs are allowed to play three over-age players in the Under-21 team, but most sides rarely do so.
“We don’t do it with 11 players. We do it with 20 players. Everybody is important," he said. “Not everybody can play, that’s the way it is.
“In Holland, it’s normal for players to play in the second team. It’s good for them. Now there’s been two away games this week, so we’ve had some good training sessions. But I still think playing in a game is much better."
In Sunderland's last Under-21 match they played the likes of Vito Mannone, Adam Johnson and Sebastian Coates and it seems that this trend is set to continue for the foreseeable future.
The change was actually proposed during Gus Poyet's time in charge, but it seems that Advocaat has been the man to make sure it happened.
Sunderland feel that not only will it keep their fringe players' match-sharpness up, but it will also help the transition for their younger players, as they will be used to playing with the first-team squad once called upon.
The Wearsiders are determined to utilise their academy graduates better in the future and they feel this is the first step to improving their youth system.