A LaLiga report has claimed that a European Super League would "destroy national leagues in the medium term," finding that a majority of clubs would suffer a 55% drop in revenue if such a competition were introduced.
The study, carried out for LaLiga by the accounting firm KPMG, argues that the league's "big two" clubs, Real Madrid and Barcelona, would be set to receive an additional €400 million each in annual income from their Super League participation.
Other Spanish clubs would suffer a 55% reduction in their revenue from audiovisual rights, sponsorship and ticketing.
Earlier on Friday Bernd Reichart, the CEO of A22 Sports Management, the company behind the Super League, insisted the latest plans for the competition would be based on "meritocracy" with "no fixed spots" for Europe's top clubs.
"The Super League isn't the format of a competition -- it's an ideological concept," LaLiga president Javier Tebas said.
"Now they've begun a new communications strategy, to add to the confusion ... The format that has been talked about would be very damaging for national leagues. It would destroy the national leagues in the medium term."
Tebas added: "This is a problem of governance. The big clubs want power in European football. We all know clubs should have more power, but every club. The Super League say clubs should be masters of their own destiny and I agree, but that's all clubs, big and small, as happens in LaLiga."
The LaLiga report -- which was presented to the media in Madrid on Friday -- claimed that the Super League would "destroy the competitive balance" in football, with a planned "semi-closed" European model for promotion and relegation which would remove the need to qualify through national league performance and therefore reduce interest in domestic competition.
"What's the worst thing for me is that they treat us like we're stupid or naive," Tebas said.
"Of course, [the Super League] is for the rich. They'll keep repeating the expression meritocracy to convince us of something that isn't true. The format they're talking about isn't just meritocracy-lite, it's not meritocracy in quotation marks, it's meritocracy in brackets."
The European Court of Justice is considering a complaint by the Super League that UEFA's role as European football's governing body in blocking the attempted breakaway league constituted an illegal monopoly under EU competition law, with an opinion from the court's advocate general due on Dec. 15.