Abramovich given demand for £10m as he watches Chelsea game

All offered congratulations except for one - which presented him with a legal document demanding repayment of a £10 million loan.

The dramatic moment at Stamford Bridge ended more than two years' efforts by the European Bank for Reconstruction and Development and its hired investigators to serve the papers on the Chelsea owner.

Richard Wallis, spokesman for the London-based EBRD, said: "The document was accepted in person by Mr Abramovich."

Asked why it had taken so long to serve it, Mr Wallis said: "If you are asking me whether it would be extremely difficult to serve on Mr Abramovich because he is surrounded by millions of bodyguards, then my answer is I don't want to comment. I'll leave it to your own imagination."

The whole saga goes back much further - to the 1998 collapse of the embryo Russian banking system.

The EBRD, created by the wealthy G7 nations, including Britain, to help former communist countries to build market economies, was lending millions to Russian entrepreneurs. Among them was oligarch Aleksandr Smolensky, who linked an EBRD-loan to his bank with a £10 million loan he had made to Abramovich's Swiss-based oil company Runicom.

Smolensky's bank collapsed and Runicom became bankrupt. But the EBRD still wanted its £10 million from Runicom and Abramovich's oil company Sibneft, sold to the Russian state in 2005.

Forty-year-old Abramovich, Britain's second wealthiest man with an estimated £11 billion, insists the money was paid back years ago.

But a Moscow court ruled in the EBRD's favour in 2002.

The EBRD then filed its claim in a Swiss court. It is understood the terms of the court order were that documents must be served personally. Mr Wallis said: "It's taken a long time but the EBRD has made every effort to deliver (the papers) as speedily as possible."

Now a Swiss judge will decide whether to hold a hearing. That may mean Abramovich facing an unwelcome court battle that could force him to open his accounts to scrutiny.

It has been a trying year for Abramovich. Although the draw against Valencia on April 4 - the night the papers were served - helped Chelsea progress in the Champions League, they were knocked out in the semi-final by Liverpool.

And recently he was divorced from his second wife Irina after 15 years of marriage.