Karl-Heinz Rummenigge wants to increase the quality of the Champions League by excluding smaller countries from Europe's biggest club competition.
The Bayern Munich CEO, contradicting previous statements, does not want a seeding structure to replace the old system.
UEFA is set to decide on changing the Champions League, and Europe's top clubs are lining up ideas to increase their share of the competition's annual income.
They aim to make the current 32-team group stage more attractive to both the biggest clubs and the TV audience around the globe.
Last month, UEFA's director of competition, Giorgio Marchetti, told AP that the governing body "need a format by the end of the year," and that it is currently in the consulting stage.
Rummenigge, the influential ECA chairman, in May already put forward the idea of making the group stages of the Champions League more attractive by deflating the competition, and restricting access to it.
In an interview with Sport Bild, Rummenigge reiterated that he is not happy with the current setup.
"It's a fact: The group stages have in the past been more attractive than they are now. I recall 1999 when Bayern played in one group with Manchester United, Barcelona and Brondby Copenhagen," he said. "Bayern and Manchester got out of the group, and also played the final."
Rummenigge said that fans are not interested in predictable group stages where "after five matches two teams have secured their berth in the knockout stages."
He said: "The fan, however, is interested in emotions. And real emotions are only generated in the knockout stages, that's where it's at. We've seen that in our incredible meetings with Juve and Atletico."
As a solution Rummenigge wants to increase quality step by step.
He said: "It needs to be discussed whether the introduction of the 'Champions Path,' which is open to every champion in Europe, also of the small associations, was a right."
In March, Rummenigge also called for a seeding structure to replace the open draw for the knockout stages of Champions League, saying that he's "had enough of fate" and "it's just common practice in tennis or other sports and somewhere along the line it has to be done."
But speaking to Sport Bild, Rummenigge said he's not "a friend of a seeding structure or wildcards."
He explained: "It might make sense in tennis, but football is different. Such things have also never been part of the discussion."