Gavin HamiltonBlackburn’s problems – as shown by the leaked letter published by Nick Harris on his website – have highlighted the close relationship that many managers and coaches now have with agents.

At Blackburn, manager Steve Kean has been given freedom to conduct transfer policy without boardroom interference. Agent Jerome Anderson has played a major role in deals – and he also happens to be Kean’s own representative. Anderson has denied benefitting financially from any transfers at Blackburn.

Over at QPR, Mark Hughes has been brought in as manager in time to sign new players in the January transfer window. Yet the most remarkable aspect of Hughes’s appointment  is not that he has moderated the ambition that saw him quit Fulham last summer. Rather that he has been re-employed by an English club at all.

Earlier this season, Hughes was a lone voice, while working as a pundit on Sky Sports, defending Carlos Tevez’s refusal to appear as a substitute from the Manchester City bench during the Champions League match against Bayern in Munich.

Hughes attracted widespread derision for his comments but he and Tevez share an agent – though he is not on FIFA’s agent list and prefers to be called a “representative” – in Kia Joorabchian.

Joorabchian is currently trying to find a well-paid home for Tevez now that the Argentinian has been shown the door by City. Already QPR are doing deals with, or being linked to, players with close links to Joorabchian. Brazilians Alex (from Chelsea) and Henrique (from Sao Paulo) are both represented by the agent Giuliano Bertolucci, a man with close ties to Joorabchian.

Of course there is nothing to stop QPR signing whoever they want, but the relationship between managers and agents is coming under greater scrutiny.

Roy Hodgson once told me that he considered his greatest achievement to have been working continuously for 20 years without an agent. At the time – this was in 1997, when Hodgson was at Inter and preparing to take charge at Blackburn – it seemed a strange thing to say. But since then, more and more managers have taken on agents to secure them work and commercial contracts.

It is by no means an English phenomenon.

In France, Jean-Pierre Bernes is the most powerful agent in the country despite his involvement in the biggest corruption scandal to have hit the French game. Bernes was the right-hand man to Marseille president Bernard Tapie in the early 1990s and spent time in prison for his part in the match-fixing that secured Marseille the 1993 French League title and European Champions Cup.

Bernes has since emerged as a hugely influential agent. His clients include current French internationals Samir Nasri, Franck Ribery, Alou Diarra and Adil Rami. More controversially, he also represents France manager Laurent Blanc and other high-profile coaches, including Didier Deschamps and Jean Fernandez.

In Portugal, one man has dominated the country’s major transfer deals in recent years. Jorge Mendes represents virtually all of Portuguese football’s major personalities, from Cristiano Ronaldo down. His coaching clients include Felipe Scolari and, of course, Jose Mourinho.

The influence of Mendes now extends to Spain, and Madrid in particular. No fewer than six clients of Mendes’ Gestifute agency – Cristiano Ronaldo, Angel Di Maria, Ricardo Carvalho, Pepe, Marcelo and Fabio Coentrao – are now in Madrid’s first-team squad.

Perhaps it’s just coincidence that last summer Real Madrid paid 10 million euros each for Nuri Sahin and Hamit Altintop, both in deals from Germany, but laid out a whopping 30 million euros for Fabio Coentrao from Benfica. All three players are at a similar stage in their careers; only one had Jorge Mendes as an agent.

There are clear conflicts of interest with the employment of agents by managers and coaches, but it is hard to see how the football authorities can intervene, especially if clubs have full prior knowledge of the agents concerned. QPR appear keen to tap into Hughes’ contacts via Joorabchian, while Madrid’s situation is confirmation of the power wielded by Mourinho at the Santiago Bernabeu. Either way, though, something is not quite right.