Rangers' former chief executive Martin Bain has had almost half a million pounds of the club's assets frozen after a judge agreed there was "real and substantial risk of insolvency".
Mr Bain is pursuing a £1.3m damages claim against his ex-employer at the Court of Session in Edinburgh.
Judge Lord Hodge granted a warrant which would ring-fence £480,000 of the Ibrox club's assets.
He said there was risk of insolvency if the HMRC tax case goes against Rangers.
Lord Hodge said that in reaching that view he was concerned with the degree of possibility and "not actuality or even probability of insolvency".
Mr Bain raised his damages claim alleging breach of contract following the takeover at Rangers FC by venture capitalist Craig Whyte from former owner Sir David Murray.
Lord Hodge said he was not persuaded on the material before him that Rangers were presently insolvent "either practically or absolutely".
The court heard that the football club faces two tax claims and the larger could leave them with a bill of £49m - £35m in tax, plus £14m in interest and penalties.
Lord Hodge said he accepted that proceedings were at an early stage, but added: "I am not persuaded that the outcome of the Revenue claim is too remote in time for the court to form a view as to the existence of a risk."
He said: "Having regard to the structure and terms of the takeover deal I am satisfied that there is a real and substantial risk of insolvency if the tax case were to be decided against the defenders (Rangers) in favour of the Revenue in the sums being spoken about."
Nicholas Ellis QC, counsel for Mr Bain, had told the court: "There already appear to be circumstances from which it would appear to be appropriate to draw an inference that the defenders are presently practically insolvent or at least verging on it by not paying their debts as they fall due."
But Brian Napier QC, for the Ibrox club, said the motion for an arrestment was opposed and claimed that Mr Bain had not shown there was a real and substantial risk of insolvency.
The chairman said they were able to meet debts as they became due.
Mr Ellis said the club's accounts for last year did show a healthy position with net assets of about £70m.
But he argued that the picture was not as healthy as shown and that was made clear in the transfer of the majority interest between companies controlled by Sir David Murray and Mr Whyte for the sum of just £1.
The deal was structured with precautions looking to the risk of insolvency.
He said there were two tax claims with the smaller for £2.8m but with penalties it could rise to about £4m.
The larger claim for a total potential of about £49m was due to go to a tribunal and he could not say what the outcome would be.
But he added: "If the Revenue are successful, given the amount of the claim, it is not at all surprising that precautions have been taken to structure the deal in a way that protected the acquirer in the event of insolvency."
He said that in the other tax case he understood £2.3m in a bank account has been arrested.
Glasgow law firm Levy and McRae also went to court over an outstanding bill against Rangers last week.
Mr Ellis pointed to it as an example of Rangers not settling their debts as they fall due.
He said the court action was clearly important to Mr Bain as an individual and an arrestment was sought to protect any award he would receive.
Rangers are contesting the action and have raised a counter claim against Mr Bain alleging breach of contract and fiduciary duties, which he denies.
Mr Napier argued that Mr Bain had held responsible positions at Rangers over a period when the two major alleged debts relating to tax liabilities were claimed to have been incurred.
He said the outcome of the tax case against Rangers could be a long way off. He argued that for there to be a real and substantial risk of insolvency it had to be "proximate in time".
A spokesman for Rangers said: "In a week where the focus should be on football, the conduct of Martin Bain, who always claimed to have the best interests of Rangers Football Club at heart, is truly astonishing and I am sure our supporters would agree.
"The club is disputing any money is due to Mr Bain and we will be vigorously appealing the decision. It should be noted the case taken against Rangers has not yet been proven or even heard yet.
"All that has happened today is that a sum of money has been set aside if the club were to lose the case."
A source close to Craig Whyte added he was "angry and dismayed" that Martin Bain had taken this action, when he claims to have had Rangers' interests at heart.
"It was clearly intended to embarrass the club in the run-up to the first Old Firm game of the season," he said.
The source also claimed the details of the counter-claim by Rangers against Martin Bain, with claims he breached his contract and duties as a company director, could be "explosive".