She has risen to become one of the most powerful women in football, but who is Chelsea transfer chief Marina Granovskaia?
Roman Abramovich's chief lieutenant operates strictly in private. She has never given a media interview and even her occasional comments to Chelsea's official website are tellingly brief, but they leave little doubt as to the scope of her authority.
When Marcos Alonso extended his contract at Stamford Bridge in October, it was Granovskaia who was quoted in the club's press release. Manager Maurizio Sarri's name was notable for its absence.
And on the odd occasion she does find herself in the limelight it is rarely out of choice and this week was no different, after Thibaut Courtois took aim to accuse her of backtracking over promises she had apparently made that he would be allowed to leave last summer.
Wondering more about how Granovskaia rose to become integral in so much of Chelsea's recent history? Read on...
Rising up at Chelsea
The Russian-Canadian has been a close ally of owner Roman Abramovich for more than 20 years. They first came into contact when she joined a Russian oil company he had just taken over in 1997. When he sold it seven years later for almost 250 times the purchase price, he had already taken over at Chelsea - and brought Granovskaia to London with him.
Over the next seven years, while she increased her influence at Stamford Bridge, success followed like clockwork. Two Premier League wins in Abramovich's first three years and five Champions League semi-final appearances in his first six soon established the club on the world stage.
Away from the trophies, Granovskaia was a long-term planner. It has been reported she was integral in building relations with Dutch club Vitesse Arnhem, who to this day act as a breeding ground for much of Chelsea's young talent. She also orchestrated the move to Chelsea's new training ground at Cobham, which opened in 2007 and is one of the best in the country.
All that helped to cement her position at Stamford Bridge, and she received the official role of Abramovich's representative in 2010. Within three years she was sworn onto the club's board, and in 2017 she demonstrated her fierce negotiating power by tying Nike into a £60m-a-year shirt sponsorship deal with Chelsea - which runs all the way until 2032.
How has she shaped Chelsea's history?
Granovskaia's final say on transfers has not always been well-received by Chelsea's managers. Antonio Conte referred cryptically to decisions by "the club" at times last season when defending his own transfer record, and successor Sarri said "the board know what I want" when his pursuit of Gonzalo Higuain looked rocky at the start of last month.
Further back, a variety of newspaper reports have suggested she was the peacemaker between Jose Mourinho and Abramovich in 2013 which allowed the manager to return to Stamford Bridge, six years after he felt personal humiliation from being shown the door by the club's owner.
"She is basically the power at Chelsea," a source quoted by the Evening Standard said of her. "Roman trusts her implicitly. She's not interested in being a celebrity but there is no doubt who's in charge and who calls the shots.
"It is symbolic of her role that she was crucial in getting Jose back. He had fallen out with Roman in very acrimonious and public circumstances and received a massive pay-off."
Granovskaia has shown her mettle in orchestrating some of Chelsea's biggest transfers of recent years. Prising Fernando Torres from Liverpool's clutches in 2011, even for £50m, was no mean feat, and neither was fighting off competition to sign Atletico Madrid striker Diego Costa after he finished just a goal behind Lionel Messi in La Liga's 2013/14 scoring charts.
Players' agents and club representatives have become used to dealing with Granovskaia for transfer business, even when technical director Michael Emenalo was still in post. It should be telling that the club was in no rush to replace him once he resigned in late 2017 - more than a year on, his office still sits empty.
Why is she in the news?
Conte might have stopped short of naming Granovskaia, but goalkeeper Thibaut Courtois wanted to be more specific in defending his reasons for leaving the club last summer in a recent interview with Belgian newspaper HLN.
He said: "That Marina is hard at negotiation is normal. The people in football who are talking about contracts, salaries, transfers, etc. that get players and dispose of them, they have the most difficult job.
"Only, in March, Marina and I had a meeting in which I indicated that I wanted to leave. Living in London and the schedule of the Premier League made it impossible for me to regularly see my children, who lived in Madrid.
'"Are you going to find something?" Marina asked me. 'Rest assured,' was my answer. "All right, then we'll let you go and we'll find a replacement."'
Courtois would later go on strike before he was allowed to join Real Madrid on Deadline Day, but his actions tarnished his reputation at a club where he had been a fans' favourite only months earlier.
Privately, Sky Sports understands Chelsea are furious at the accusation from their former player and vehemently deny them - but don't expect a public response from Granovskaia any time soon.