Roberto Martinez has questioned the reasoning of Stuart Attwell's decision to send off Gary Caldwell but is not planning an appeal.
The Wigan defender was dismissed for a foul on Carlos Tevez in Monday night's 3-0 defeat to Manchester City which Attwell adjudged to have involved a two-footed challenge on the Argentina striker.
Martinez was furious with the verdict after the match, saying that Attwell was 'lying' for making a decision on something he did not see.
The Latics boss has now tried to explain why he was so upset after being contacted by the Football Association about his strongly-worded comments.
"It is an important situation to clarify," he said on Sky Sports News. "You can agree or disagree with a referee's decision, that is part of the game.
"I will never question a referee's decision, but what I was really disappointed with was the reasoning of that decision.
Hard to take
"It was clear to see and everybody will have their own opinion on whether it was a red card offence or not, but the reasoning was that it was a two-footed challenge by my player.
"It is quite clear that was not the case. If anyone goes two-footed it was the opposing player, and that is why there was disappointment and anger."
Martinez added "I never had a problem with a referee's decision. It is a tough job and you have to make decisions in a split second.
"But when the reasoning is something that didn't happen, it is a lot harder to take."
Martinez, who is now preparing a formal response to the FA, refused to be drawn on whether he stood by his use of the term 'lying'.
"We will answer the letter to the FA and we have to make everything quite clear," he said.
"I know exactly the incident and I know the reasoning of the referee, and it is quite clear that is something that did not happen in the challenge."
Martinez does not feel Wigan would be successful in contesting the decision, claiming that Attwell's report refers to the challenge only as being of 'excessive force'.
"Unfortunately the report shows a different situation so I don't think we will be able to appeal," he explained.
"What it says is it was a challenge using excessive force, which contradicts his first reasoning of the red card.
"In the report it doesn't come across as a two-footed challenge so that makes it even harder to explain. A very bizarre moment."