Madrid, Jan 24 : Real Madrid are the first sports team to earn more than 500 million euros in a year, according to a study.

Real top the so-called money league for a record-equalling eighth year in a row with 512.6 million euros in revenue, ahead of fierce rivals Barcelona in second and England's Manchester United in third.

"With expansion of the club's Bernabeu home planned, and further commercial revenue generating opportunities available, Real are likely to be difficult to displace at the top of the money league, in the near future at least," research firm Deloitte, who studied the subject, said in a statement, Wednesday.

Despite Real and Barcelona's success, they were the only Spanish teams in the top 20, thanks to a system that allows La Liga teams to negotiate their own TV deals, concentrating wealth in the hands of the biggest clubs.

Among five English teams in the top 10, Manchester City posted the biggest leap in revenue, up 51 percent in a year to 285.6 million euros, enough for seventh place.

The world's top 20 are drawn exclusively from Europe's biggest five leagues - England, France, Germany, Italy and Spain.

Deloitte said the upcoming 2014 World Cup in Brazil and 2018 World Cup in Russia could give clubs from those countries a valuable financial and infrastructure boost to enable them to compete with the global elite.

"Clubs from these countries potentially have a strong platform to challenge the dominance of clubs from Europe's 'big five' Leagues, and hence enter the lower half of our top 20, in future years," the study's authors said.

Revenue for the world's top 20 football clubs has quadrupled in the last 15 years as the value of TV rights deals has soared.

The study is based on the clubs' financial statements. Deloitte said they did not conduct any independent verification work.(IANS)