MADRID - Spanish football clubs Real Madrid and Barcelona are the two biggest earners in world football according to the annual findings published by Deloitte this Thursday.

The bank discovers that Real Madrid is the biggest earner in football for the sixth consecutive year, with income of 438.6 million Euros ($597 million). They are closely followed by FC Barcelona, with the Catalan club earning 398.1 million Euros a year.

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Barcelona could theoretically overtake Real Madrid next year when they 30 million Euros a year short sponsorship deal with the Qatar Foundation comes into effect, along with the increased popularity Barcelona enjoys thanks to the profile of World Cup winners, Andres Iniesta, Xavi Hernandez and the club' s Argentinean star Leo Messi.

The two Spanish clubs head the list thanks mainly to the manner in which television rights are negotiated in Spain with each club carrying out separate negotiations. Madrid and Barcelona earn over three times more than any other club in Spain. This helps explain why the only other Spanish club in the top 20 earners is Atletico Madrid, which sneaks in in 19th place among the top earners.

Manchester United is third in the list and is the highest placed of seven English clubs among the top 20. The greater overall power of the English game is due partly to the fact that in the Premier League negotiates its rights collectively, with much smaller differences between top and bottom earners.

It should also be pointed out that Deloitte's figures refer only to earnings and do not reflect whether or not the clubs made a profit or loss over the season.