Premier League referees have been warned over their conduct after retired official Mark Halsey discussed his friendship with Alex Ferguson.
Contact between referees and managers is prohibited on the grounds of professional integrity but, in extracts from his soon-to-be-released autobiography, Halsey has revealed that he and the former Manchester United boss exchanged text messages.
Halsey explained that he once contacted the Scot in order to urge him to defend fellow official Mark Clattenberg over allegations of racism towards Chelsea midfielder John Obi Mikel in October 2012.
Though he insisted that his impartiality was never threatened by the pair's relationship.
He wrote: "I took matters in my own hands and rang Sir Alex asking him to speak out. He agreed and used his Friday press conference to say he could not conceive of Mark (Clattenberg) saying such things.
"It helped the situation a great deal. It took time to gain Sir Alex Ferguson's respect but in the end we had a very good relationship.
"One thing should be made clear about my relationship with Sir Alex. I may have spoken to him a lot and shared texts but he knew when I crossed that white line there were no favours.
"Players and managers would not respect you if you gave decisions based on friendship."
Halsey's revelations have since led refereeing body Professional Game and Match Officials Ltd to issue a stark warning to its members regarding its professional code.
A spokesman for PGMOL told The Mirror: "At the beginning of the season all our referees were reminded of the importance of adhering to these important PGMOL protocols.
"This covers a number of issues, including making direct contact with managers and players, which for integrity reasons is prohibited. Any new publicity will only heighten awareness of adhering to these important PGMOL guidelines."
Halsey's autobiography also discusses the threat of suicide among officials who are placed under the strain of refereeing in high-pressure circumstances in the Premier League.
"There is no hiding place on the field and you have to be mentally tough," he said. "But it also follows you off the field more and more now and it can destroy you,"
"I do feel that referees should get more help to cope with the increasing level of mental strain. In my view, given some of the episodes of recent seasons, it will not be long before a referee has a nervous breakdown.
"I also believe that if we do not do something to help referees with mental health and stress issues, then we could see a suicide."
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