Postecoglou admitted that his players had wilted in the intensity of their third World Cup game .
Postecoglou said they had learnt the hard way that lapses of concentration would be brutally exposed at the highest level .
Admitting that his players had wilted in the intensity of their third World Cup game , Postecoglou said they had learnt the hard way that lapses of concentration would be brutally exposed at the highest level .