Is Hackett right to criticise referees in public?
Much has been said about referee Steve Bennett and his sending off of Javier Mascherano for dissent.
However, no-one has considered that on the morning of the match Bennett got a very public ticking off by his boss Keith Hackett. How much did this colour his refereeing of the Manchester United versus Liverpool clash?
After the match I went back to Hackett's column in the Sunday Telegraph which centred on Bennett being the fourth official in the Tottenham versus Chelsea midweek match where Ashley Cole's horrendous foul on Alan Hutton merited only a yellow card not a straight red.
He took Bennett to task in no uncertain terms.
Hackett, who is the general manager of the Professional Game Match Officials Board, selects referees for matches and had chosen Bennett for the Old Trafford match and Mark Clattenburg for the Chelsea versus Arsenal match because as he put they both "show maturity and calmness in pressure situations".
However, much of his article was as blunt a criticism of a referee as I have ever read. If a player or manager had made it he could well have faced an Football Association charge.
He excused referee Mike Riley from blame over the Cole incident because he did not "have the best viewing angle afforded to him".
But Hackett could find no excuse as to why Bennett did not help out Riley.
"It was unfortunate that Steve didn't come in to say to him that it was a red. I'm waiting to discover why the two of them didn't have the trust in each other to come to the right decision because when I looked at the screen I automatically thought the player was off. It was over the top, committed with excessive force and endangered the safety of the opponent," said Hackett.
Hackett's anger was all the greater because he has fitted all match officials with communications systems to help them to talk to each other.
Bennett was also dammed in Hackett's eyes because he is a very senior referee and the only possible reason Hackett could think of for Bennett's failure to do his job was that he was distracted by his other duties in the technical area.
I understand Bennett may at the time of the incident have been busy trying to put up the board saying how much injury time would be played, as the incident came towards the end of the first half.
I do not know if Bennett read these words over his cornflakes before he went out at Old Trafford but if he did then there can be little doubt that his antenna would have been up to make sure he did not earn more rebukes from his boss.
Mascherano certainly did not help his cause but Bennett was clearly in no mood to take prisoners.