Canterbury coach Dean Pay has been hit with a massive $25,000 fine for his post-match criticism of the NRL referees last week.

Pay pointed the finger at the referees following their controversial 22-20 loss to Brisbane at Lang Park on Thursday night, hinting at a conspiracy against the Bulldogs.

NRL head of football Brian Canavan said that Pay had impugned the integrity and performance of the referees and "went beyond the acceptable parameters".

Pay blasted a number of calls but was most livid about a "ridiculous" 79th-minute decision to send Bulldogs full-back Moses Mbye to the sin-bin for a professional foul, gifting Brisbane the match-winning penalty.

Mbye was sent from the field, just as golden point beckoned with scores locked at 20-20.

"I got a group of blokes who busted their arse and to be decided like that, it's ridiculous," Pay said on Thursday night.

"I will follow it up with them [the NRL] and they will say, 'We got it wrong', and they will just move on — it doesn't help us.

"We are trying to win a game of footy here and get our season going forward and it's decided like that."

Pay added: "It's like we are not supposed to win."

He also took issue with Brisbane's Jamayne Isaako not being pulled up for an alleged knock-on and Bulldogs prop David Klemmer being marched for back-chat.

Pay was not happy that Klemmer was penalised for back-chatting when he approached referee Gerard Sutton as stand-in skipper with captain Josh Jackson on the bench.

It gave Brisbane a 52nd-minute penalty that locked up the scores 14-14.

"It's the way he speaks to my players as well," Pay said.

"He [Sutton] didn't even ask him if he was captain at the time. Dave said he was [captain] but was penalised for back-chatting.

"He wasn't aggressive towards him. He was asking a question."

NRL referees boss Bernie Sutton on Friday declared that his men had got all three decisions - including the Mbye sin-binning - correct.

Pay, who is the first NRL coach to be sanctioned for comments about refereeing this season, and the Bulldogs have five business days to respond to the fine notice.

In past seasons, $10,000 has been the usual fine for coaches overstepping the mark.

But during last year's finals the NRL sought to clamp down on ref criticism when Cronulla's Shane Flanagan was fined $30,000 and Manly's Trent Barrett copped $20,000.

AAP