Trent Robinson launched a scathing attack on referee Ben Cummins and the NRL bunker in the aftermath of Sydney Roosters' 20-18 defeat to St George Illawarra Dragons.
The Roosters slipped to a seventh loss in eight NRL matches this season after just falling short in their bid to overturn an 18-point half-time deficit at Allianz Stadium.
But head coach Robinson was left seething with what he considered several "soft calls", and was particularly riled by a penalty given against Dylan Napa for a high tackle on Dragons' debutant Taane Milne who, alongside Boyd Cordner, left the game with concussion.
Robinson was critical of the NRL bunker - the league's video referral system - and did not hold back in his criticism of Cummins, who he labelled "disrespectful".
"The bunker has decided to be the on-field ref today and they jumped in at every occasion," Robinson said at his post-match news conference. "They're not the match review committee.
"We're on Anzac Day [a day of remembrance to commemorate Australia and New Zealand war heroes] and we want to play a tough game and they were just soft calls coming from a bunker.
"Ben has been horrible and disrespectful to our players for many years. We've had good high percentage win rate up until this year and with Ben Cummins we've won two games under him.
"He speaks poorly to our players and he won't look them in the eye. The way he spoke to Jake [Friend] during the game was unacceptable.
"Two guys had a head clash - big play in the game - I don't know if we would have won. St George might have defended well and held on. That was a big play."
Robinson was asked if he would contact referees chief Tony Archer, but stated he expects to hear from the NRL first for his outburst.
"I'd say [NRL chief executive] Todd [Greenberg] might be ringing me. That might be a start. [But] you have to create change," he added.
"You don't want to walk in here and make excuses about the game. We lost it in the first half because we didn't play well enough.
"But I'm also not going to sit here and allow poor decisions to go by because of a rule and not allow referees to talk to players the way they should over years."