Andre Villas-Boas does not see any reason to apologise for his comments about Chris Foy after being asked for an explanation by the Football Association.
Chelsea have been charged with failing to ensure their players conducted themselves in an orderly fashion against Queens Park Rangers at the weekend, while Villas-Boas must respond to the FA over what he said in his post-match media remarks.
The Blues were given until Friday to respond on both counts, after which Villas-Boas could be hit with a charge for accusing the referee of not treating both sides equally and of being 'card happy'.
Villas-Boas admitted on Sunday that he was 'very aggressive' with Foy after accosting the official post-match, having watched Jose Bosingwa and Didier Drogba dismissed and seven more of his players booked at Loftus Road.
That landed Chelsea with an automatic £25,000 fine, which is bound to increase if they are found guilty of the FA charge.
Villas-Boas, who claimed referees had been unfair to his side during previous games this season, could also end up fined or even suspended for his post-match outburst.
But speaking shortly before the FA announced they were taking action against the Blues, the 34-year-old stood by his words, something that could land him in even more trouble.
"I don't think I said anything I shouldn't have," Villas-Boas said.
"I would never question the referee's integrity.
"But the fact is that, at the moment, we are paying heavily in terms of major decisions.
"Maybe this is what the FA (don't) want to hear from me - phrases like, 'The referee has influenced heavily three of our games'."
No Bosingwa appeal
Villas-Boas accepted officials were only 'human' but reiterated his attack on what he claimed was inconsistency in Foy's 'extremely unfair' decision-making.
"If you go one route, you have to stick to it for the rest of the game," he said.
"With 11 players, we should have played better and there are mistakes we have to avoid and which are fair - you have to be criticised and evaluate yourselves and learn from those mistakes - but it's a very disappointing day for the referee, for Chris Foy. I will stick to my words."
He added: "Chris, for this particular game, was card happy and didn't show a pattern to what he's done in the past.
"What happened in that game was surprising given what he'd done before."
Villas-Boas revealed he had called referees' chief Mike Riley to complain about officiating for the second time this season, but did not think it would have any effect.
He elected not to appeal Bosingwa's controversial sending-off for a last-man challenge, with the right-back's one-match ban ruling him out of Wednesday night's Carling Cup fourth-round tie at Everton.
Villas-Boas, whose side host Arsenal in the Premier League on Saturday, said: "It might have put us in trouble for the Arsenal game, appealing Bosingwa's red card, and we weren't going to use him in the Carling Cup anyway."
Ashley Cole is also suspended after picking up his fifth booking of the season, while Drogba will serve a three-match ban for his two-footed tackle on Adel Taarabt.
Despite his side racking up a further six yellow cards at Loftus Road, as well as their fourth red of the campaign, Villas-Boas denied Chelsea had a discipline problem.
"It's not indiscipline, it's not aggressiveness," he said.
"There might be tactical fouls, that you have to allow. You have to respect.
"We didn't ever lose our discipline. We committed fouls because we were exposed, but that's not indiscipline."
Villas-Boas also hit back at QPR midfielder Shaun Derry's claim that Chelsea 'lost their heads' on Sunday, and branded suggestions they had been bullied as 'ridiculous'.
"Fantastic Shaun Derry," Villas-Boas snapped sarcastically.
"You could ask Shaun Derry whether, playing against nine men, they might have done a bit better.
"Full praise to their commitment and to their strength, but they don't have to blow it out of proportion because we won't."