It was the day when Rangers fans registered their disquiet as another civil war was brewing within the corridors of power at Ibrox.

A demonstration saw more than 100 supporters visiting some 10 Sports Direct stores around the country to try to buy baskets of high value sports products for a symbolic £1.

It reflected serious concerns over Sports Direct owner Mike Ashley and the strengthening of his power base at crisis-hit Rangers while also owner of English Premiership side Newcastle United.

The method of the protest mirrored disbelief by some that the Buckinghamshire-born entrepreneur managed to secure the naming rights of Ibrox for just £1 - which could see him rename the ground Sports Direct Stadium, if he wished, like he did with Newcastle's St James' Park ground.

The protest organised by influential fans group Sons of Struth focussed on the Sports Direct store in Glasgow Fort but was echoed around the UK at stores in Warrington, Edinburgh and Ayrshire.

The unrest at Ashley's football business activities in Glasgow is echoed amongst Newcastle United fans and it is understood a group is planning a similar protest in Newcastle before the next club home game.

Craig Houston at Sons of Struth said: "The message about our concern has gone out before we even started today. And the protestors will grow in number and there is an appetite for more."

The fans group has already announced plans to boycott this month's League Cup quarter-final clash with St Johnstone as they bid to have controversial shareholder Sandy Easdale, a supporter of Ashley, removed from Rangers International Football Club Plc's subsidiary football board.

Sources at Uefa, European football's governing body, have indicated that the billionaire entrepreneur's involvement as owner of Newcastle and a major shareholder with influence at Rangers may breach rules surrounding the integrity of their competitions including the Champions League and the Europa League. Uefa regulations state that no individual or legal entity may have control or influence over more than one club participating in a UEFA club competition. That includes being able to exercise "by any means a decisive influence" in the decision-making of the club

While the issue would only come into play if the two clubs qualified for a UEFA competition, fans of both clubs are known to be concerned that Ashley is now placed in the conflicted position of choosing where his interests in terms of pushing for lucrative European competition would lie - with Rangers or Newcastle.

The Union of Fans (UoF), a coalition of Rangers supporters groups has already written to Scottish football's governing body, the SFA, asking them to "rigorously enforce" strict rules on dual ownership.

Ashley has an agreement with the SFA limiting him to a stake of no more than 10 per cent in Rangers.

But Article 13.1 of the SFA Articles of Association state that no person involved in another club "has any power whatsoever to influence the management or administration of a club" without "prior written consent".

Ashley has previously shown by his control of Newcastle United that he will not bow to fan pressure and has flexed his muscles by calling an extraordinary general meeting to force another revolution on the board of RIFC plc, with the removal of chief executive Graham Wallace and director Philip Nash.

His influence extends beyond the boardroom, having also struck a deal for the operation of the club's shops and controlling a portion of Rangers' revenue through the contract which sees club merchandise sold through his Sports Direct chain of stores.

Influential Newcastle and Rangers fans and observers perceive that Ashley's game plan is to establish his Sports Direct brand to a worldwide audience - through the massive television exposure of the Champions League.

Rangers becomes an attractive proposition because the cost of players required to win the Scottish Premiership - with a route into Europe's lucrative top club tournament - is a fraction of that which would be required to take Newcastle anywhere near the top four Champions League qualification places in the English Premiership.

It is felt Rangers would then provide the most realistic and cheapest route of the two clubs to get the Sports Direct brand onto the European stage.

Ashley has already indicated he would consider selling Newcastle United, but not until the end of next season.

The concern of key figures within the Rangers and Newcastle United supporter base is that Ashley's main interest is not in the growth of the clubs he is involved with, but the expansion of Sports Direct.

Since November 2009, when Newcastle's St James's Park was renamed to Sports Direct, its share price was steady at around £1. It is now six times that value.

Ashley has taken Newcastle United from a loss-making business, recording an annual loss of £32.9 million before he took the reins, to a concern turning a profit for the third successive year in 2012-13.

But his critics point to a slump in commercial revenue, which includes all sponsorship deals, from over £25 million when he took over to £17.1m six years later - at a time when most top flight football clubs are showing great growth.

Rangers fan groups have already criticised Ashley for failing to plough the £850,000 he recently spent on shares into the crisis-hit club.

When the Newcastle owner bought 4.26 million in shares through his MASH Holding vehicle, more than doubling his stake, he did so from existing shareholder investment company Hargreave Hale through two intermediaries - rather than through RIFC's recent open offer aimed at raising £3.6 million. The latter option would have directly benefited the financially struggling club's fundraising effort.

Chris Graham of the UoF, which supports an alternative direction through former Rangers director Dave King's offer to re-invest up to £50m in the club, said: "There is no question he has a conflict of interest.

"This is not about the fact we don't like Mike Ashley, our view is based on the problems there have been in Newcastle, and that we have an alternative.

"Our worries are that commercial deals are being done in such a way that it benefits Sports Direct and not Newcastle and that we will see that at Rangers. It is astounding what he has done at Newcastle, because he is actually like a leech sitting and [he] creams the money off through Sports Direct.

Steve Cole, chairman of Newcastle United Supporters Club in London said: "I think there is a conflict of interest here but most, if not all, Newcastle supporters I speak to are desperate for Ashley to jump ship and jettison Newcastle in favour of Rangers.

"With the level of investment it is clear that under his ownership the club will never break into the top four and Champions' League football.

"St James's Park has become a massive advertising hoarding for Sports Direct - all free advertising of course. The feeling amongst fans is that Rangers will inevitably be back in the Champions League within the next two to three years and Ashley, if forced to choose between the two clubs, will go with Rangers to enable him to take his Sports Direct brand to a wider worldwide audience."

Mr Cole, who sits on the Newcastle United fans liaison forum added: "One thing I will say about Mike Ashley is that he did pull the football club back from the brink of financial ruin and has put us in a state of financial security and I truly believe that had he been properly advised and with just a little more ambition , we could have challenged the top four here in England. "But sadly he doesn't share the passion or understand the mindset of the average Newcastle supporter and I fear it will be the same if he takes total control at Rangers."