Newcastle United owner Mike Ashley was accused of insulting the Islamic faith when in a bar in Dubai a decade ago, a judge has said.
Detail of the allegation has emerged in a ruling on the latest round of a High Court dispute involving Mr Ashley, who also owns sportswear firm Sports Direct, and former Charlton Athletic co-owner Tony Jimenez.
Mr Ashley has sued Mr Jimenez over a 2008 French golf course deal and says he is owed £3 million.
Mr Jimenez, a former Newcastle United vice president, disputes his claim.
The judge, Chief Master Matthew Marsh, analysed a number of legal issues at a pre-trial High Court hearing in London in October and published a ruling relating to those issues on Wednesday.
He had been told about a 2008 "disturbance" at the Bahri Bar at the October hearing and has given more detail relating to "allegations about the events" in his ruling
The judge said Mr Ashley had been accused of making remarks which "included insults" to the Dubai Royal Family and the Islamic faith and its followers, and to former Newcastle manager Kevin Keegan.
Mr Ashley had said he "may have made a 'regrettable' remark".
Barrister Adam Johnson, who leads Mr Jimenez's legal team, had told Chief Master Marsh, at the hearing in October, that Mr Ashley's "basic complaint" was that he was entitled to be repaid £3 million he handed over with the aim of acquiring an indirect interest in the Les Bordes golf course development.
Mr Johnson said Mr Ashley had given instructions for £3 million to be paid into a nominated company account, but had subsequently agreed that the money should be "retained" in relation to work Mr Jimenez had done trying to find a buyer for Newcastle United.
He said Mr Ashley also agreed to hand over another £7 million.
Mr Jimenez said he had done a lot of work on the Newcastle sale and became "increasingly concerned" after Mr Ashley refused to meet a potential buyer, who went on to buy Manchester City.
He had lined up further potential buyers and Mr Ashley had visited Dubai between September 13 and 18 2008 in order to meet them, Mr Johnson had said.
"Mr Jimenez says that on the evening of 16 September 2008, Mr Ashley created a disturbance in a bar in Dubai," Mr Johnson told the judge.
"'Although Mr Jimenez helped Mr Ashley minimise the impact of the trouble, it again ruined the potential sale of Newcastle United Football Club that Mr Jimenez had lined up."
Chief Master Marsh added in his ruling: "The defendants fairly submit that Mr Ashley was slow to engage with the allegations about the events on 16 September 2008 and that his initial account was guarded.
"He now says that he may have made a regrettable remark in the Bahri Bar, directed towards those with whom he had been in negotiation earlier that day."
The judge said: "Mr Jimenez says Mr Ashley made remarks that were much more widely directed and included insults to the Dubai Royal Family and the Islamic faith and its followers, and to Kevin Keegan."
He said it was "common ground that steps were taken by Mr Ashley to manage the way in which the event was reported" but said there were "significant differences of recollection about the effect of the events".
"Mr Jimenez says Mr Ashley was shaking and saying he and his business empire faced ruin," said the judge.
"Mr Jimenez says Mr Ashley came to see him at 4 am on 17 September 2008 in a panic worried about being locked up in Dubai and facing adverse press reporting in the UK."
Barrister Richard Lissack, who leads Mr Ashley's legal team, had told the judge at the October hearing that £3 million had been transferred "at Mr Jimenez's direction for him to hold" for Mr Ashley for the "agreed purpose of securing a shareholding in Les Bordes".
Mr Lissack said Mr Ashley was entitled to the repayment.
He said it was "inherently improbable" that Mr Ashley would have "agreed to have gifted Mr Jimenez £10 million".
The judge indicated that issues would be further analysed at another hearing.