I was watching Groningen vs Ajax from the Dutch Championship, and the way Groningen were bringing the ball forward against the mid block of Ajax caught my eye. Both wingers were creating an overload in midfield when the ball was with the central defenders or the holding midfielders, while the three midfielders were constantly changing positions in the central zone.
The whole move happened between 6:41 and 6:51 in the game. Here is a video of the movement of the players:
One of the Groningen holding midfielders moves a little bit deeper than the striker of Ajax, who is following the movement of the ball.
Starting position of the midfielders: The No 8 is on the same side as the defender with the ball, the No 10 is on the same side as the No 6.
None of the 3 midfielders are on the same vertical line. The No 10 is the most central, the No 8 is a bit more outside than he is. The two central defenders are in the widest positions.
This is a great way to position themselves, it guarantees the most passing options for the central defender and the No 6.
When the No 6 gets the ball the No 8 stays in position, closer to the ball than his opponent. The No 10 moves on the other side of his opponent. This way if the No 8 gets the ball, he has two passing options, No 10 and No. 11.
When the central defender gets the ball Ajax start pressuring. This is the moment the players nearest to the ball must help. The No 6 and No 8 move deeper, closer to the ball.
The full-back on the strong side also moves deeper along the sideline. Otherwise both full-backs are positioned even higher than the second holding midfielder.
If the ball is with either of the central defenders or with one of the holding midfielders facing the Ajax goal, the winger on the ball side is positioning himself in a free passing lane. If the ball is with either central defender, the wingers never enter the central zone. The winger on the weak side comes only until the edge of the central zone.
All this time the No 9 is high up the pitch. This provides depth for Groningen, which is essential in order for the wingers to have space between the lines for free movement.
When the No 11 sees that the ball goes to the No 6, he immediately runs wide. When the No 8 can turn towards the Ajax goal, he immediately looks for the winger on the sideline. By the time the No 8 is put under pressure by the recovering No 8 of Ajax, the Groningen winger has to be as high and wide as possible, facing the Ajax goal.