Professional Footballers' Association chairman Clarke Carlisle has given his backing to a new Premier League crackdown on player and manager misbehaviour but warned there must be no grey areas in the new rules.
The top-flight clubs have announced a new campaign targeting "unacceptable" behaviour towards referees and criticism of officials to run alongside the Football Association's Respect campaign.
PFA chairman Carlisle, who plays for Burnley, said: "As long as the guidelines are clear we will support them. They need to make sure there are no grey areas so that referees can apply them consistently and players know where they stand."
Carlisle said the PFA's annual meetings with the Referees' Association had shown there had been a drop in the number of incidents involving players, and claimed that when incidents did happen they were blown out of proportion.
He added: "The number of incidents where referees are accosted are becoming fewer and fewer. It is just that where incidents are highlighted they now receive massive, global attention.
"But the key is to make the guidelines clear because it can be a very emotive issue if it is subjective and incidents appear differently to different people."
Carlisle said the new crackdown was not a sign that the Respect campaign had failed.
"Respect has not failed at all," he said.
"The Referees' Association themselves have agreed the number of incidents - and the scale of the incidents - is reducing.
"It is definitely not failing but we are always looking to improve the image of the game."