The post mortem after any Old Firm defeat is usually extensive. When it's a mauling like Rangers suffered at the hands of their rivals and champions Celtic at Parkhead then it's likely to be quite deep.
Giovanni van Bronckhorst admitted he was at a loss to explain how his side could concede goals from areas of specific danger they had highlighted from the Hoops. Namely, the fact Ange Postecoglou's men are quick-thinking and the Light Blues weren't alert to it.
The Dutchman will now try to find answers to that. But issues run deeper than that. To lose in such a manner could almost be accepted if it was a one-off. It has happened to managers over the years - Dick Advocaat when Van Bronckhorst was a player and went down 6-2 at Parkhead. Martin O'Neill who lost 5-1 at Ibrox. But the problem for Van Bronckhorst is that it was a repeat performance of his derby dug-out debut at Parkhead back in February. And failing to learn from mistakes is a bigger issue.
