London, Oct 16 Following Sir Alex Ferguson's apology to Alan Wiley, referees' chief Alan Leighton claims that managers' would now think twice before abusing or arguing with officials.

Ferguson had apologized in a last-ditch attempt to escape a misconduct charge for his verbal attack on Wiley, the referee, during Man U's 2-2 draw at home to Sunderland.

"If we had not challenged Alex Ferguson over his comments, it would have lowered the bar even more in terms of the criticism and abuse referees face," The Mirror quoted Leighton, as saying.

"We couldn't allow that to happen and what has happened over the last week or so has started to redress the balance," he added.

Leighton reckons that referees are always under pressure to perform well, and urged that rather than pressurizing them, referees should have a free hand while making decisions.

"A referee can have a good game, then make one decision a manager, players or fans disagree with and it all goes off like Krakatoa! It's as if the referee has just committed a murder," Leighton said.

"When you get on a bus there's a sign at the front which says threatening, violent or abusive behaviour towards the driver will not be tolerated. I'm not saying we should ban or eject everyone who has a go at the referee, but there has to be a line drawn in the sand," he added. (ANI)