Vulnerable defense not just lose games, but also lose team bonding and confidence. Building a defender is big part of the game. It has to be serious and fun as well.
In this drill, one defending team vs 2 possession teams. The game starts with a build up at the first zone with only one pass allowed for the team in possession in that zone. The defenders will have to press high. Once the ball transferred to the possession zone, the forwards aim to pass through the gates to the opponents in their build up zone. If the defenders win the ball, they also have to pass through the gates to the opponents on their zone. Then move to defend again. You might choose different build up tactics on each side to subject defenders to different situations. In the possession zone, the forwards have to finish in set seconds, thus putting more pressure on both sides.