The Portuguese was angry with Graham Salisbury - who replaced injured official Andy Davies - after Kieran Lee was denied a late penalty after going down as he drove past Hoops defender Grant Hall. And Carvalhal insisted that he could not understand the decision not to give his side a spot-kick.
"I have tried not to talk about the referees since the beginning of the season," he told the Star.
"I have talked with Kieran Lee. I believe in him 300 per cent. He is a very serious guy. If it wasn't a penalty, he would have told me.
"After talking with him and seeing the image, it was a very clear penalty. It was an unbelievable decision. It could have made a big difference of course as there were three or four minutes left in the game."
While the 1-1 scoreline sent the Owls up to fifth in the table, the side's form since the turn of the year has been so impressive that their last two results could be classed as something of a slump.
Before the draw with Jimmy Floyd Hasselbaink's men, Wednesday had lost to Preston North End, and while it is certainly too early to suggest that their hopes of remaining in the play-offs have been significantly dented, Carvalhal may now be worried about how long it will take for the side to wrestle back the momentum they need to keep their spot in the top six.
And with two of the top four ahead in their next three games, Carvalhal could be forgiven for letting his frustration boil over as he would have viewed the game against Rangers as one of their better opportunities in the coming weeks to consolidate their position in the promotion race.