Who do you want to win, Roman?

Tkachenko has been friends with Abramovich since they met at the 2002 World Cup in Japan and, as a life-long football supporter, played a small part in recommending certain players following his purchase of Chelsea last summer.

A genial man in a sharp pin-striped suit, Tkachenko is reluctant to discuss his role as a football consultant but happy to describe the scene in the Ibrox dressing room.

He said: "Chelsea is Roman's main devotion but he has a soft spot for CSKA. I was in the dressing room with him when they beat Rangers and we all offered the team congratulations. Giner invited us into the dressing room and I'm sure he'll do the same tonight. Roman wants all Russian teams to do well and was delighted by the result. He was very happy but was keeping mum.

"Roman has been to a lot of CSKA games and could be of great help to Mourinho! If they need someone to provide a scouting report then he could do it.

"I'm not sure if Roman is a CSKA supporter, but if they were playing my team he'd want them to win because of his company and his friendship with Giner."

Abramovich's oil company, Sibneft, sponsor the club to the tune of £ 10million a year - more than two-and-a-half times the value of Chelsea's contract with Emirates - and he has pledged to spend £40m on building a new municipal stadium. After the criticism that followed his extravagant investment in Chelsea, Abramovich has had the good sense to realise that charity should begin at home.

The Sibneft sponsorship deal caused uproar when it was announced last March and triggered UEFA's conflictof-interest inquiry following the Champions League draw in August, but in the context of Russian sport it is nothing exceptional. Five of the country's 16 Premier League teams are backed by big businesses in a sport that is becoming increasingly corporate, with Dynamo and Spartak Moscow funded by Yukos and Lukoil respectively.

Furthermore, Dynamo president Alexei Fedorychev has links with Monaco through their shirt sponsorship deal with his chemical company Fedcom. Something else for UEFA to think about.

In his large wood-panelled office on the top floor of the company's headquarters, in a 19th-century merchant's house with a view of the Kremlin across the Moscow River, Sibneft president Euguene Shvidler explains the background to the CSKA sponsorship.

As Abramovich's right-hand man, the 40-year-old was chairman of Chelsea for about a week last summer, before refocusing his energies on the company he runs with an iron fist.

A short, stocky and aggressive individual, this billionaire has no time for the conspiracy theories that have come his way since the Chelsea takeover.

Shvidler said: "It's a big sponsorship deal but the picture is skewed completely, they're comparing apples and oranges. They don't compare the right things and should compare the entire budgets.

"They say it's bigger than Manchester United's but it's almost half of CSKA's entire budget. Russian clubs get very little money from television, tickets and shirt sales so sponsorship is crucial. This social responsibility is very important for sport nowadays.

"The business picture in this country is changing, it's getting more important to pay more taxes and invest in the country generally.

"It was a corporate decision taken at boardroom level. In the end the choice of club was easy as CSKA were the champions and we wanted the best team.

"If they'd finished second last season we probably would've picked them because we're close to the owners."

In a rare moment of levity, Shvidler confesses some excitement at tonight's meeting with his old friends.

He said: "This game will be extra special as we have many good friends on both sides.

"We're very close friends with the CSKA owners and they're Chelsea sympathisers who've been to many games.

"I wouldn't say that Chelsea are much better or the favourites. CSKA have some very good players. I never predict the score but know it's going to be a very good game. I don't care who wins and want both of them to advance.

"At the moment it's too early to say what the best result will be and after the first game it will be much more clear." Shvidler is not the only one in Moscow with divided loyalties and Chelsea's Russian revolution has spawned thousands of new true blues.

The Chelsea Russian Fanclub, who ironically received their official certificate from Russophobe Ken Bates at the start of last season, have four branches throughout the country, with more than 600 members in Moscow.

Even the disappointment of Saturday's defeat to Manchester City cannot dampen the enthusiasm in the Metelitsa Casino on the Novy Arbat, where Chelsea's Russian fans gather to watch their team every week.

Fanclub press officer Ivan Skornik said: "The Abramovich takeover has at least tripled the number of Chelsea fans in Russia as we're a very patriotic people.

"Chelsea are a great club with a long, aristocratic history and it's great that a Russian has bought them. It's impossible to count the number of fans."

CSKA supporters are also grateful to Abramovich and, with their side facing a potential Championship decider against FC Zenit on Saturday, would not be too dismayed by a defeat this evening.

UEFA, Porto and Paris Saint-Germain may not agree, but home wins for both clubs over the next fortnight would keep everyone happy.