Pressing trigger is clear in training and disappears in games

The trigger may be fine. The supporting distances are probably the bigger test. In training, everyone knows the exercise is about pressing, so the midfield is already expecting the backward pass. In a real game they are processing many more things. I’d coach the players around the striker. When the backward pass travels, can the nearest midfielders move early enough to take away the easy next pass? If they are still ten yards away when the striker arrives, the trigger will look wrong even if the striker read it correctly. Use a directional game where the pressing team can score quickly after a regain, but do not tell them when to go every time. You want the players to recognise the shared picture. The first player can’t press on their own; training has to show the whole group why the moment matters.