Real Madrid president Florentino Perez on Thursday decried a European investigation into state aid for seven clubs, saying the allegations were an unwarranted campaign against Spanish football.
Perez hit out a day after the European Commission launched a probe into seven Spanish football clubs, including Real Madrid and Barcelona, after complaints they had accepted illegal state aid.
Brussels is notably looking into whether Real Madrid, Barcelona, Athletic Bilbao and Osasuna benefited unduly from their status as associations owned by their members, which pay a 25-percent tax rate instead of the usual corporate rate of 30 percent.
The European authorities also want to know whether the clubs enjoyed unfair exemptions from social security contributions and tax debts.
"I think there is a campaign against Spanish football and I think it is bad," Perez said in unscheduled comments during a Madrid breakfast conference organised by Spanish news agency Europa Press.
"The difference between the corporate tax rates of 25 percent and 30 percent has been so damaging to Real Madrid," Perez said.
In the past 10 years, Real Madrid had to pay to the taxman an extra 13 million euros ($18 million), which it could have deducted as a reinvestment if the club had been set up as a normal company, Real's president said.
Financially, Real Madrid's status as an association was thus "a negative", he said.
Perez criticised, too, the Commission's investigation into a 2011 property transfer between Real Madrid and the Madrid city hall, saying the deal had already been thoroughly probed.
"There has already been a complaint. There has already been an investigation. They have already tried to harm us. And nothing happened," the club boss said.
The European Commission said the land swap was "very advantageous" for Real, with a plot of land owned by the club being valued at 22.7 million euros, up from a 1998 estimate of 595,000 euros.
Spain's secretary of state for sport, Miguel Cardenal, said the allegations had hurt Spanish sport.
"The image of Spanish football and Spanish football has been seriously tarnished. That is the reality," he told the same conference.
The alleged tax advantage for Real Madrid, Barcelona, Athletic Bilbao and Osasuna over the last four fiscal years amounted to 1.6 million euros in total, he said.
"If the complainant is right, the enormous scandal we are talking about amounts to 100,000 euros per team per year," Cardenal said.
"It is preposterous to believe there has been state aid."