Alan Thompson was sent off for a tackle on Nacho Novo

Dougal's decision to give a straight red instead of a yellow incensed Neil Lennon so much that the Celtic captain was himself red-carded after the game.

But McVicar said: "The criteria was made perfectly clear to clubs.

"Any tackle that endangers the safety of a player must be considered serious foul play and a red-card offence."

The referee will also take into account such things as aggression, intent, the speed of the tackle and the match atmosphere.

But McVicar believes Dougal was "absolutely correct" to send off Thompson in a match eventually won 3-1 by Rangers.

There was the intent and there was aggression SFA referee's chief Don McVicar

Dougal's decision following the lunge at Rangers' Nacho Novo mirrored several red cards shown the previous weekend at the start of the Premiership season in England.

"The referee did the job he had to do and the job the SFA wants him to do," said the head of referee development.

"I would consider Thompson's tackle on Novo to come into the career-threatening category.

"There was the intent and there was aggression.

"The referee was criticised for showing too many cards, but his only fault was that he possibly didn't show enough cards."

McVicar would not talk about the specifics of Lennon's dismissal, which followed remarks the midfielder made to the referee at the end of the game.

The Celtic captain went on to barge Dougal - and has since apologised for his actions on his club website.

"I don't know the exact details of what was said and I would not wish to comment on heresay," McVicar told BBC Sport.

"Foul language, known as industrial language, is often accepted.

"But when it becomes abusive or insulting to the referee, that's when action must be taken."

Dougal's report is expected to be received by the SFA on Monday and will go forward to the next disciplinary committee.