Spanish giants Real Madrid have topped Deloitte's Football Money League for the 11th consecutive year, generating 577m euro (£439m) in 2014-15.

Champions League winners Barcelona are second with 560.8m euro (£426.6m), with United third on 519.5m euro (£395.2m).

But Deloitte said there was a "strong possibility" United would overtake the La Liga sides in next year's edition.

What is the Deloitte Football Money League?

The professional services firm's sports business group produce an annual table of the clubs with the highest revenues.

The combined revenue for the top 20 clubs in the table rose by 8% from last year to 6.6bn euro, a new record.

Manchester United slipped from second to third in the table following a year-on-year drop in revenue, but Deloitte said the Premier League club's "strong commercial growth" and "ability to agree impressive new sponsorship deals" such as the £75m-a-year Adidas kit agreement, compensated for a lack of European football last season.

United's position "emphasised the strength of their business model", added Deloitte and with the new £5.1bn television rights deal starting from 2016-17 season, Real Madrid would come "under increasing pressure" next season and in future years.

The wealth of the Premier League - mainly due to strong broadcasting deals - means 17 Premier League clubs feature in the top 30, with West Ham making the top 20 for the first time since 2005-06, with revenues of 160.9m euro (£122.4m).

Will the bubble burst?

Manchester United topped the first Deloitte Football Money League in 1998, with an overall revenue of £87.9m.

The report's author, Deloitte partner Dan Jones, was part of the team that compiled that table 18 years ago, and recalls being asked then whether football's financial model was sustainable.

"I still think this is a growth market," he said.

"If anything, there will be a small acceleration of growth in the next few years. It might level off a little bit, but that is what it will be rather than any sort of decline."

The usual suspects

Real Madrid, Barcelona, Manchester United and Bayern Munich have been a constant presence in the top five since 2008, while runaway French league leaders Paris St-Germain have been in the top five for the past three years.

Bayern slipped two places to fourth this year, while the Premier League's bigger clubs pack the next level.

Manchester City remain in sixth place, while Arsenal moved above Chelsea into seventh and Liverpool sit ninth.

Champions League runners-up and Serie A winners Juventus complete the top 10.

AC Milan were regulars in the top five in the early years of the report, taking third position in three successive years from 2003 to 2005.

However, the Italian club dropped out of the top 10 two years ago and slipped two further places to 14th this year.

Manchester United's slip to third is a direct consequence of their failure to qualify for last year's Champions League, but Deloitte says they could return to the top next year even though they were eliminated from this season's competition at the group phase.

Their position in the list comes largely as a result of a commercial operation that continues to generate record sums.

However, United have not won a trophy since Sir Alex Ferguson's retirement in 2013 - and Jones expects the Old Trafford club to slip down the money table in future years if their barren run continues.

"You can be successful off the pitch even if you aren't successful on it for a time," said Jones.

"The reason why Manchester United is able to be so commercially successful is because they had an incredible 20-year run of on-field success.

"I am not surprised to see Manchester United up there and challenging to reclaim that number one spot they lost 11 years ago. But I don't think that is a long-term sustainable position if they don't get more things going for them on the pitch."

(BBC)