The transfer season's real power players

Forget the star signings – money-men, agents, scouts and 'advisers' hold the aces in football's biggest deals. So who wields the greatest influence of all?

1. Florentino Perez

And in the first week the Real Madrid president said, "Let there be Kaka, and there was Kaka." No wonder supporters are now holding their breath for Cristiano Ronaldo, David Silva, David Villa and Franck Ribéry.

It's the second coming of the former Real Madrid player to whom one-time club vice-president Emilio Butragueno once sycophantically referred as "a superior being". Perez looks set to upset the transfer apple-cart just as spectacularly as he did the first time.

He broke the world record to sign Zinedine Zidane in 2001 a year after taking Luis Figo from Barcelona. Ronaldo and David Beckham were added in 2002 and 2003 as he went about building the most sponsor-friendly football team on the planet. He now wants to do the same again.

A roads engineer by trade, Perez heads the construction company ACS, whose turnover in the first quarter of 2009 exceeded €4bn (£3.5bn). He is reckoned to be worth in excess of €600m but it is his shrewd political brain and his quiet but ruthless determination to get what he wants, not his personal fortune, that Madrid supporters believe can put them back on top.

He was a local Madrid councillor for the centre-right Central Democratic Union party before moving into football and the alliances forged as a politician have served him well. In 2003, he wiped out the club's entire debt in one go by selling Real's old training complex to the local council for a favourably high price, cutting through red tape and buying a couple of business towers on the redeveloped land in the bargain. He admits his close relationships with Milan's Silvio Berlusconi and Adriano Galliani have smoothed through the Kaka transfer for a lot less than Manchester City offered in January. Now attention switches to Ronaldo. "The key is that all the big players I signed wanted to come, it's 90 per cent of the battle," he says.

2. Tony Stephens

Stephens is one of football's best-known names thanks to his representation of Alan Shearer, David Beckham and Michael Owen. Yet he could walk down the street unnoticed. Biographical facts on Stephens are deliberately kept to a minimum. He is either 55 or 56 and has two grown-up daughters. Photographs are rare, particularly recent ones.

Stephens is famously circumspect in his dealings with the press, despite the profile of his three top clients. More than 20 years ago this was not the case. Stephens was the sales and marketing director of Wembley Stadium and before that he ran the commercial department at Aston Villa. But in 1988 Stephens set up an agency, TSA, and once he got Shearer on board he began to acquire a reputation for thoroughness and financial straightness. TSA was bought by a New York company 10 years later and was then bought again by the multibillion SFX agency. SFX had an office in Mayfair but it is thought the secretive Stephens still operated from Solihull. It is now part of the WMG Group. With Owen and Shearer facing uncertainty, it could be a busy summer for Stephens, who once wrote a book: The Sunday Footballer.

3. Kia Joorabchian

A university dropout whose father was a car dealer. So far, so clichéd. But this 37-year-old, best-known for his partial ownership of Carlos Tevez, is an exotic creature. Tehran-born, but exiled when the Iranian Revolution broke out while the family were in London, he has also lived in Canada and the United States, where he ran an early hedge fund. He became involved in Brazilian football at Pele's suggestion and, via the company Media Sports Investments, bought Corinthians, signing Tevez to them. The experience turned so sour he was made the subject of an international arrest warrant for alleged money-laundering in 2007 by a Brazilian judge. Joorabchian denied the charges and a year later the warrant was suspended. By then, MSI had brokered the arrival of Tevez and Javier Mascherano to West Ham. While it is not clear if Joorabchian still owns any rights to Tevez he remains the player's agent and will be an influential figure in determining the Argentine's club next season now his loan at Manchester United has expired.

4. Martin Ferguson

Appointing your brother to a senior scouting post may look like nepotism, but Martin Ferguson would not have kept his job as Sir Alex's most trusted transfer adviser for a dozen years if he did not deliver. Martin played and coached in Scotland before joining Manchester United to scout players and opponents. Among his early recommendations was Diego Forlan. While that did not endear him to United fans the Uruguayan's subsequent record suggests that Ferguson can pick a player. Jaap Stam and Anderson are subsequent signings. Ferguson is known within the game for his encyclopaedic knowledge of players and if his elder brother decides to strengthen this summer, it will be Martin he calls first.

5. Garry Cook

The man from Nike covered himself in opprobrium when he crudely criticised Milan and Kaka's father over Manchester City's abortive bid for the Brazilian but he is not as stupid as his public pronouncements sometimes suggest. City's executive chairman is the link between Sheikh Mansour bin Zayed al-Nahyan, who owns the club via the Abu Dhabi United Group, and Mark Hughes, the manager. As such, Cook is heavily involved in the club's lavish summer spending plans. The 46-year-old Birmingham City fan was with Nike in America for 12 years and, while he sometimes lapses into US commercial speak, the signs are he is gradually absorbing the lessons of the Kaka debacle.

6. Jorge Mendes

The man who spotted Cristiano Ronaldo when the player was 16 could be one of the big financial winners this summer if his No 1 client moves to Real Madrid. "Sometimes I breakfast in London, lunch in Madrid and have dinner in Milan," says the man who moved Jose Mourinho to Chelsea in 2004. It is all a far cry from his first deal shifting goalkeeper Nuno, who he met in the nightclub he owned, to Deportivo La Coruña from Vitoria de Guimaraes in 1997.

An average left-sided midfielder for Portuguese third division side Vianense Mendes is said to have shown an early business acumen by taking over the selling of pitch side advertising for the club. He now has Nani and Anderson at Manchester United and central defender Pepe at Real Madrid. The antithesis of his No 1 client, the 43-year-old is fiercely protective of his privacy and has only given one interview in the last decade, to the Portuguese daily A Bola.

7. Dr Sulaiman al-Fahim

The ambitious 31-year-old property billionaire from Dubai (left) is just itching to spend some money once his £60m takeover at Portsmouth is confirmed. With a personal fortune of £3.5bn, he has targeted a top 10 finish next season for Pompey, which would necessitate transforming the club's somewhat threadbare squad.

He is certainly not afraid of parting with his cash. This is the man who fronted the Manchester City takeover last summer – and immediately broke the British transfer record by signing Robinho for £32.5m from Real Madrid. He also had a bid of £30m for Dimitar Berbatov accepted by Tottenham, only for the player to opt for Manchester United.

A source close to the billionaire said: "His principal ambition is delivering success. There is no doubt he will want to move quickly to do that. The doctor is a charismatic figure who does not like to hang around. When he has a task he likes to get on and do it. You have to remember this was the man who organised the Manchester City takeover, and then immediately delivered Robinho."

Fahim is likely to rely heavily on Thai dealmaker Pairoj Piempongsant, a 53-year-old former teacher who brokered the Portsmouth takeover and last summer's Robinho transfer. Piempongsant is also heavily involved with the Abu Dhabi United Group, which owns Manchester City.

8. Pini Zahavi

The "super-agent" – as he is dubbed in the tabloids – is a former sports journalist who has been involved in many of the biggest and most controversial moves in recent years.

From his modest office in Tel Aviv, the 55-year-old has built up the most extensive contacts book in world football – and an estimated fortune of £60m. He still represents some players, such Joao Moutinho of Sporting Lisbon, who could be moving to Everton, and Rio Ferdinand, whose £30m move from Leeds to Manchester United in 2002 earned Zahavi £1.1m.

But more importantly he is called in to broker deals because he knows pretty much everyone in world football. He helped Roman Abramovich buy Chelsea in 2003 and Alexandre Gaydamak buy Portsmouth in 2006.

He still advises Abramovich on an occasional basis, and has been used as Mr Fix-it by Abu Dhabi United Group. When Wayne Bridge moved from Chelsea to City for £13.5m in January this year, Zahavi pocketed £900,000 from the deal.

9. Stéphane Courbis

The French agent who represents the Arsenal striker Emmanuel Adebayor is one of the most oft-quoted men in his profession. Barely a day has passed these last two summers when he hasn't spoken to some media outlet in Europe or Africa about the future of his client.

He is a regular visitor to matches at the Emirates, where his loose-tongued approach to his job has angered many key figures, not least the manager, Arsène Wenger, who met Courbis this week to discuss Adebayor's future.

Insiders at Arsenal accuse Courbis of making trouble and unsettling the Togo striker, and cite the way the agent openly invited Milan to bid for the player last summer as evidence.

Courbis, who is based under Fifa's noses in Nyon, Switzerland, has a history of causing chaos with the Gunners, having masterminded the departure of Robert Pires on a free transfer to Villarreal in 2006.

His father, Rolland Courbis, is one of the most controversial figures in French football. The former Marseilles coach was sentenced to two years in prison for taking backhanders in transfer deals more than 10 years ago. Courbis Snr has yet to serve the term as he is appealing and recently led Montpellier to promotion to Ligue 1, before quitting last weekend.

10. Eugene Tenenbaum

Tenenbaum is the man Abramovich has trusted above all others for more than a decade. A 44-year-old Russian who grew up in Canada, Tenenbaum is seen as the "good cop" but still does much of Abramovich's bidding, such as sacking the former manager Claudio Ranieri on the phone in 2004.

As Abramovich's closest aide, Tenenbaum will be closely involved in the club's transfer dealings this summer, as the purse strings are loosened for the first time in three years. He has already featured in Chelsea's so far unsuccessful pursuits of both Kaka and Ribéry, but is not the kind of guy who likes to leave his boss disappointed for long.

He has been a key figure at Chelsea since Abramovich bought the club six years ago, when he became one of the three directors. But his position has strengthened in recent months as speculation increases that the chief executive, Peter Kenyon, is considering his future at the club.

It was Tenenbaum who advised Abramovich to sack former coach Luiz Felipe Scolari in February, while Kenyon was on holiday in Barbados.