Wages at Premier League clubs have shown a worrying 11% leap to £1.3billion overall, according to an annual report of football finance.
Business analysts Deloitte's report claims the rise is a concern because wages last year accounted for 67% of the turnover of all 20 clubs - a notable increase after a decade where the proportion had stayed between 58% and 62%.
Experts believe the change could pose a problem to the English top flight with UEFA's new rules saying that from 2012 clubs in European competition will only be allowed to spend what they earn.
The clubs' wage bill rose by £132million over the previous year and Dan Jones, director of Deloitte's Sport Business Group, said that should act as a warning - especially in the light of Portsmouth being forced into administration by over-spending.
Jones told Press Association Sport: "The wages increase is definitely something people should be concerned about, and that will be even more the case when the UEFA initiatives are in full swing.
"This report clearly shows there is an issue there to be dealt with.
"The revenue story is still very positive and has proved resilient to the recession but the clubs have to get costs under control."
Reliance on 'sugar daddies' such as Manchester City's Sheikh Mansour is also increasing.
The report states: "A model of profit maximisation is now pursued by a very limited number of clubs and, whilst some clubs seek to break even on a consistent basis, the emerging norm for many Premier League and Championship clubs appears to require significant ongoing benefactor support.
"As such we appear to be seeing a continuing shift from a sustainable 'not for profit' model towards one with potentially calamitous consistent and significant loss-making characteristics."
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