Leicester chief Rob Kelly rounded on referee Andy D'Urso and assistant Carl Bassindale after the 1-0 defeat to Derby.
Kelly was incensed that a late strike from Elvis Hammond was disallowed for handball, as Derby claimed a 1-0 win thanks to a Jon Stead goal.
It is believed that the effort was chalked off for a handball, but Kelly was left in the dark after confronting D'Urso after the final whistle.
"It was a goal, I have seen the video and I cannot see a handball," said Kelly.
"I do not know why the linesman stuck his flag up because I am not inside his head.
"We do not pester officials when their decisions go against us but I tried to ask the referee why the goal was disallowed - he would not speak to me. I asked the fourth official and she told me the linesman had seen a handball.
"Decisions like that knock the stuffing out of you and you hope they even themselves out over the course of the season.
"But just recently we have been on the end of several unbelievably bad decisions and they always seem to be away from home."
Rams chief Billy Davies did not see the penalty incident, as he noted: "I asked my players and they said there had been a handball.
"If the video shows there was not then it is unlucky for Leicester."