Don has left the 24 select referees who are to take charge of all top flight matches next season in no doubt of the stance they should take.

And he will be meeting coaching staff from each Premiership and Football League club to warn them in advance.

"In law, foul and abusive language is a sending-off offence," explained Don.

"What we are saying is where it is wilfully directed at the match officials we expect the referee to take action.

"If it is wilfully directed, the only action a referee can take is to dismiss, he cannot caution.

"If it is foul, abusive or insulting, then that is a sending-off offence.

"What I'm saying to the referees is if it's a spontaneous remark then have a quiet word with the player.

"What I've said to them is that I don't want them going overboard at the beginning of season, going out there looking for trouble.

"If it is wilfully directed at the ref or the assistant ref, then really we expect the referees to take action."

Don has taken into account the pressure players and managers are under and will emphasise the need to distinguish between incidents.

He added: "We don't want referees to over-react.

"There is a very fine line between what is frustration and what is dissent.

"Dissent is a cautionable offence, not frustration.

"But if they step over that line, and frustration becomes dissent, then that's a caution, and if the language is wilful and is directed at them, then that's a dismissal offence."

Don also wants the fourth official to play more of a role in games.

He said: "It happened with John Gregory and others last season and we're asking the fourth officials to be more pro-active and more vigilant.

"They get quite a good fee for acting as a fourth official in a Premiership game and I think they need to earn their money a bit more.

"I would imagine that the fourth official will give the manager or the coach two or three opportunities to stay in the dugout.

"We don't want them to over-react. My view when I refereed is that the game is the most important 90 minutes of the week for that coach, so to ask him to sit down with his finger on his lips for 90 minutes is absolutely crazy.

"Football is an emotive game."