Uefa insists there is a long way to go before it decides to rubber-stamp plans to allow domestic cup winners entry to the Champions League.
Lex Gold is unhappy at Michel Platini's idea
The Scottish Premier League has said it will oppose the tentative plans.
SPL chairman Lex Gold told the Daily Mail: "We would oppose vehemently any move to push Scottish Cup holders into the Champions League."
But Uefa spokesman William Gaillard said: "There is still a long way to go and the status quo could remain."
Gold continued: "We would not want to see that happen at the expense of the SPL runners-up and are making representations."
New Uefa president Michel Platini is giving thought to ways of making the elite club competition more attractive and competitive.
Uefa has stated that a makeover will not go ahead without support from clubs, leagues and national associations.
While handing us one thing, Uefa are looking at taking something else away
But the SPL is determined to preserve the present system, with its two leading teams going into the Champions League.
Uefa Cup places are currently allocated to the third-placed team and the Scottish Cup winners.
"One of the proposals on the table from Platini's people is for cup holders to play off against each other for Champions League entry," said Gold.
"That would be at the expense of our second place, which currently goes to the runners-up in the SPL.
"I was told we would have an automatic place in the group stages for our champions.
"But, while handing us one thing, Uefa are looking at taking something else away."
It would need the agreement of the clubs, leagues and national associations
Uefa spokesman William Gaillard
Gold also fears that Scottish teams could lose their seeded status in Champions League qualifiers.
But Gaillard added: "Many ideas are circulating of contrasting views and this one is that the cup winners from countries with more than one qualifying team for the Champions League would go into the tournament.
"It would need the agreement of the clubs, leagues and national associations.
"So, if they support it, it will go forward.
"There is still to be a debate and meetings will be held at the end of August and a final decision made in September.
"It still has to be endorsed by the Strategic Council and approved by the Executive Committee."