Ricky Stuart stated that Nick Cotric should not have been expelled despite the dangerous launch on the center of Draghi Tim Lafai.
Stuart was fired during the post-match press conference, saying he believed Cotric was on the move because "at the moment there is a lot of noise regarding fair play".
"I don't think it was a foul, it was an accident," he said.
"Anyone who thinks it's a spear, doesn't know about the rugby league game.
"It was not intentional, but [the tackle] if it got away a little and I understand it, it's an accident.
"The boy [Lafai] played, Nick has no malice in him at all.
"It ended up with him in the wrong part of this, as far as he was expelled. I just thought it was very hard.
"My heart turned to him because I know how much it will hurt."
Stuart said the Raiders would fight the issue once the game was reviewed on Monday.