NRL head of football Graham Annesley has told referees' bosses the level of errors in recent weeks is unacceptable.
Annesley was particularly concerned referees Adam Gee and Gavin Badger allowed play to continue in Newcastle on Saturday night after recognising Warriors centre Peta Hiku suffered an injury and reaffirmed they were aware of the NRL directive to stop play for serious injuries.
The referees were reminded of the policy after Grant Atkins and Badger did not stop play during the round-five match in Townsville after Cowboys winger Nene Macdonald fractured and dislocated his ankle in a collision with teammate John Asiata.
However, play was again allowed to continue at McDonald Jones Stadium on Saturday night until Sione Mata'utia scored a try for the Knights, despite Badger pointing towards Hiku as he staggered out of a tackle and telling Gee to "watch him".
"They were aware that he had suffered a head knock, they were aware that he was on the ground and they should have stopped play at that tackle before the play-the-ball. They had time to do that," Annesley said.
"He said 'watch him', in other words 'keep an eye on him' but that is not good enough. That is saying 'I have identified that there is an issue there so keep an eye on him'. Well, keep an eye on him is not the right answer. Stop the game and have him assessed is the right answer.
"It is a very serious error in that we hold clubs accountable for dealing with suspected head injuries and we hold them accountable to a very high degree. We know from the audio that they identified this, they just didn't take the right action at the right time."
It wasn't the only error in the match to leave Annesley frustrated and he said Ken Maumalo was incorrectly denied a try by NRL Bunker officials after they watched a camera angle that cast doubt over whether the Warriors winger had control of the ball as he grounded it.
The first camera angle confirmed Gee's call that Maumalo had correctly ground the ball and Annesley said review officials did not need to view any further angles.
"The other angle cast doubt in their mind about their initial thoughts and they didn't need to do that," Annesley said. "That's a training issue that management of the Bunker have to deal with."
A penalty against Adam Blair for stripping the ball from former Warriors teammate Mason Lino was also incorrect as it had been a loose carry and should have been ruled a knock-on. Instead, the Knights scored on the next set.
Annesley also revealed match officials in Friday night's match at Bankwest Stadium should have awarded Wests Tigers another set of six tackles after a chargedown by Victor Radley.
A touch judge later failed to detect Joseph Manu had put his foot into touch before a Sydney Roosters try.
Annesley was due to meet separately with the referees and their coaches later on Monday.
"I need to get comfort from the people I have to hold responsible for the performances of match officials," he said.
"The one thing we can't stop is mistakes but some of mistakes over the last couple of weeks simply aren't good enough and they are mistakes that shouldn't have been made so we need to try to find out why and what they are doing to hopefully ensure it doesn't happen again leading into the finals.
"That is what coaches do week in and week out, they don't accept errors from their players and they work on strategies and ways to try to make sure those mistakes aren't repeated.
"I need a level of comfort from their coaches that they have this under control."
On a positive note, Annesley said the Bunker had spotted Cronulla playmaker Kyle Flanagan kneeing Brisbane's Matt Lodge in the head during Sunday's match at Pointsbet Stadium and advised referee Matt Cecchin, who was initially going to penalise the Broncos prop for retaliating.
Flanagan was charged with grade-one dangerous contact and had entered an early plea which enabled him to escape suspension and play in Saturday's match against Melbourne.