Furious fan groups have rounded on their own clubs over a "blatant power grab" ahead of proposed Champions League reforms.
Rangers and Celtic will keep a keen eye on a Friday meeting that could sign off on a proposal to increase the number of matches in the tournament to 225 per season.
Andrea Agnelli, chairman of the European Club Association of which Celtic 's Peter Lawwell is a member, insists the revamp is the "ideal" way forward for the competition.
Under the new format, each team would play at least four extra group stage matches and provide Europe's most successful with a safety net should they miss out the Champions League via their domestic divisions.
However, it's reported some ECA members are still pushing for greater commercial control of the new competition.
An open letter to Agnelli, signed by Manchester United, Arsenal, Bayern Munich, Real Madrid and Ajax fans, among others, insists supporters are being ignored.
It reads: "We are writing to you on behalf of them and millions of others across the continent who you have chosen to ignore in your attempt to take over European football.
"Your plans to restructure the Champions League by increasing the number of games, introducing qualification based on past achievements, and monopolising commercial rights present a serious threat to the entire game."
The letter continued: "Instead of realising your supposed goal of 'building a successful, sustainable, and socially responsible football industry', you will only make the gap between the rich and the rest bigger, wreck domestic calendars, and expect fans to sacrifice yet more time and money.
"All for the benefit of whom? A handful of already wealthy clubs, investment firms, and sovereign funds, none of which have the legitimacy to decide how football should be run. Even most ECA members stand to lose out from the proposed reforms.
"Such a blatant power grab would be indefensible at the best of times, but at the height of a global pandemic, it is nothing more than crisis profiteering - not to mention a stark contrast to the solidarity displayed by fans."
The ECA board meeting will be followed by a gathering of UEFA's club competitions committee.
The fans' letter warned that clubs should sideline fans at their peril.
It continued: "Over the past year, we have supported our clubs unconditionally, buying season tickets with no hope of attending games, and paying for TV subscriptions to watch repetitive ties held in empty, soulless stadiums, all while you were working behind the scenes to find new ways to bleed us dry," it read.
"But we do not have the time or money to invest in your fantasies or fund your insatiable greed. And in the end, we are your business model.
"Despite the expectations of some, there is no 'fan of tomorrow' waiting to come off the bench to rescue your plans.
"We are the fans of today, and we do not want more European games. We want strong, competitive domestic leagues, an equal opportunity to qualify for Europe based on sporting merit, and fairer sharing of the game's wealth.
"We therefore demand that you drop your reckless plans. We also call on football's governing bodies to stop making concessions to elite clubs and intervene to protect the future of the game."
The committee is dominated by ECA representatives, who include Manchester United executive vice-chairman Ed Woodward and Manchester City chief executive Ferran Soriano.
Only approval from that committee will enable UEFA's ultimate ruling body, the executive committee, to make a final decision on the new Champions League format on Monday.
