I’d make the whole team responsible for the balance, not just the 6.
If the 8 breaks forward and both full-backs are already high, somebody else needs to recognise that your rest defence is becoming thin.
The 6 is usually central to that, but the opposite 8 may hold, one full-back may delay their run, or a winger may stay connected to the next transition.
I’d coach a simple picture: before another player joins the attack, how many do we already have beyond the ball and what remains behind it?
Use a directional game where the defending team gets a bonus for scoring within a few seconds of regaining. That quickly exposes moments where six attackers have gone forward with no protection.
Attacking freedom is good.
The team just needs shared responsibility for the spaces left behind.
At U15, I want the players to start seeing that one teammate’s forward run changes the job of several others.
