Manchester United has been ranked football’s most valuable team by Forbes magazine for the sixth straight year as a group of investors and fans try to buy the heavily indebted club.

The American business magazine’s valuation is $1.8 billion, but the Glazer family owners are resisting the hostile Red Knights campaign to buy the 18-time English champions and their debt of $1.1 billion.

Based on Forbes’ estimation, which takes into account revenue growth, profitability and debt levels in the 2008-09 season, United is the most valuable sports team in the world.

Real Madrid is second in the football list at $1.323 billion, with Arsenal third at $1.181 billion - the same top three as last year.

Barcelona has leapt to fourth from seventh after winning the Champions League plus a Spanish league and cup double last season, taking Bayern Munich’s place after the German side’s value dropped by 11 per cent to $990 million.

Liverpool, which is sixth at $822 million, is looking for a buyer and its American owners Tom Hicks and George Gillett Jr. are confident that their off-field activities this year have increased the value of the club despite being unlikely to qualify for the Champions League next season.

The top ten is completed by AC Milan ($800 million), Juventus ($656 million), Chelsea ($646) and Inter Milan ($413 million).

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