After Roman Abramovich pulled off a similar stunt at Chelsea last month, the mega-rich Abu Dhabi businessman - whose estimated worth is £560billion - has transformed the club's huge debt into equity.
Party time: High-flying Manchester City are now debt free
Enlarge Delight: A fake banknote celebrating the Sheik's investment at Man City
The release of City's yearly financial figures - that came peculiarly late last night - underlined how far they have to go if they want to take their rivals' Barclays Premier League crown.
City were bought by the Sheik Mansour's Abu Dhabi investment company in August 2008 and have subsequently spent more than £200m on players in a bid to break into the Premier League's top four.
With their revenue streams not greatly different from previous years - City have not yet had the benefit of Champions League income to bolster their finances - the world's richest football club lost £92.6m for the financial year ending May 31, 2009.
Expensive: Robinho and Carlos Tevez were costly acquisitions
'The financial results reflect a period of rapid change at the club, the result of long-term planning and investment by the board and owners, to create a sustainable business in the future,' said City's chief financial officer Graham Wallace.
Splashing out: Sheikh Mansour
'The owners' decision to convert debt to equity is in line with their previously-stated financial strategy and is fantastic news for supporters of Manchester City, whose club is now on a secure financial foundation that gives a tremendous platform to build from in the future.'
The Sheik's outlay is down in a document filed at Companies House on Christmas Eve.
The £305m includes some debt he inherited when buying the club from Thaksin Shinawatra, as well as the purchases of star players like Robinho, Carlos Tevez and Emmanuel Adebayor.
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