CNN  — 

Chelsea manager Jose Mourinho is never one to shy away from the headlines – but the man who paved the way for the English Premier League club’s success story has always remained firmly in the background.

Chelsea finishes its English Premier League season on Sunday when its captain John Terry will lift the gleaming silver trophy after the game against Sunderland.

Up in the stands smiling at the sight of his players celebrating will be Roman Abramovich – the Russian businessman with an estimated fortune of $9.1 billion, who has revolutionized the club since arriving in west London 12 years ago.

Under Abramovich, Chelsea have become a major player in world football – winning the European Champions League in 2012 and attracting some of the most talented players on the planet.

And while an air of mystery still surrounds a man who purchased the club for $233 million in 2003, those who have been fortunate enough to play for Chelsea say his vision to transform the club was evident from the very beginning.

“He loves the game, he has a general football culture,” Marcel Desailly, the former Chelsea captain, told CNN.

“He doesn’t speak to the media but I can tell you he knows what he’s talking about when he talks about football.

“He’s the one that directs his directors on the choice of the coaches, on the choice of the players, because he knows about football.

“He was very humble, very simple but clinical when he was having words with you and asking you ‘what you think about this player, do you think we should do this?’”

Desailly arrived at Chelsea in 1998 from AC Milan where he had won the Champions League and two Italian titles.

He remembers Abramovich’s arrival and the message which was being conveyed at the time by those close to the Russian.

While the public perception was one of caution and skepticism, Desailly says Abramovich’s arrival was greeted with delight by those within the squad.

Desailly recalled: “I remember Peter Kenyon who was the director at the time saying: ‘Guys don’t think that we are just coming to bring a few pounds and go away.’

“He said: ‘We have a lot of money to build up the academy, to develop the training center and to last for a long time because Abramovich really has a 15-20 year plan for the club.’

“We were very pleased and not surprised about what was happening, knowing that I had the luck to be captain under Abramovich, knowing that he is passionate about football.”

Chelsea’s triumph in this season’s Premier League is the fourth the club have won since Abramovich arrived at Stamford Bridge.

Three of those titles have come under the stewardship of Jose Mourinho, the Portuguese coach who is in his second spell at the club.

But this year Chelsea has faced accusations that the brand of football it plays has been “boring.”

While it faltered in its pursuit of the Champions League title, losing to Paris Saint-Germain in the last-16, its progress towards the domestic crown was almost faultless.

And although some of Chelsea’s football may not have always been scintillating, Desailly, who won the 1998 World Cup and European Championship finals in 2000 with France, rejects the view that it was boring.

“I think it is the opponent which has behaved differently in front of Chelsea,” Desailly added.

“They knew Chelsea was the sort of team to be playing on the counter attack and have changed their approach to the game.

“Chelsea have stuck to its skills and to the discipline that Mourinho has set from the beginning.

“Chelsea has played well, sometimes it has played bad, but at least it has performed well in a football perspective.

“You cannot blame Mourinho because he has set a team in that aspect.”

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