Manchester United were relaxed this evening about the deal which saw Paul Pogba’s agent allegedly earn £41m by delivering the Frenchman back to Old Trafford, despite suggestions that Fifa would seek “clarification” of the transfer in light of revelations in a newly-published book.

United said that Fifa “have had the documents since the deal last August” and certainly feel the deal is legitimate, despite an AFP report that it would be investigated by the governing body. United have been unwilling to comment on Raiola’s cut from the deal, chronicled in a new book, based on the research of Der Spiegel journalists Rafael Buschmann and Michael Wulzinger and published in Germany this week. The club says it does not comment on contracts.

The club are very aware that Fifa, as regulator, must be seen to be examining deals which have raised questions in the public domain, though what the book really reveals is the extraordinary power wielded by agents, who can negotiate with impunity, however big the club and manager . Raiola claims he told Sir Alex Ferguson in 2012 that a new deal Manchester United were proposing for his then 19-year-old client Pogba was “an offer that my chihuahuas wouldn’t sign.” He took Pogba to Juventus.

The book, ‘Football Leaks: the Dirty Business of Football’, discloses the eye-popping £367,640-per-week ‘basic’ Manchester United salary of Raiola’s most lucrative client, Zlatan Ibrahimovic, rising to £422,500 on account of the £2.86m bonus he receives for scoring 28 goals in his first Premier League season.

But Raiola’s earning power is just as extraordinary. The £41m allegedly includes a near £23m cut of the transfer fee and five instalments totalling £16.39m from United over the course of Pogba's five-year contract.

Other Football Leaks documents reveal Raiola negotiated a deal for himself which would earn him millions of pounds if United’s bid for his client Henrikh Mkhitaryan was rejected last summer – as well as a huge sum if he left for Old Trafford.

Manchester United summer transfer targets Show all 8 1 /8 Manchester United summer transfer targets Manchester United summer transfer targets Ivan Perisic, Inter Milan United want to spend £35m on Perisic but Inter are holding out for closer to £50m. That said, Mourinho is a big fan and may be willing to go the extra mile to get him. Likelihood: 7/10 Getty Manchester United summer transfer targets Renato Sanches - Bayern Munich Sanches was being chased by United before deciding on Bayern Munich last summer but is back on their radar again 12 months later. He is available for £43m and Ancelotti has admitted United are "a possibility". Getty Manchester United summer transfer targets Fabinho - Monaco An extremely versatile player Mourinho sees him more as a defensive midfielder and could be used to give Paul Pogba, last summer's big addition, more freedom. Monaco aren't in any rush to lose any more first team stars this summer though and are likely to demand a hefty fee. Likelihood: 7/10 AFP/Getty Images Manchester United summer transfer targets Eric Dier - Tottenham United have already had a bid less than £25m rejected for the defensive midfielder and know they must more than double it to have any hope of signing Dier, who is understood to want the move. Getty Manchester United summer transfer targets Nemanja Matic - Chelsea Nemanja Matic has twice worked under Jose Mourinho before and he wants to make it a third time at United. However, after beating Chelsea to Romelu Lukaku, relations between the two clubs have been soured somewhat. Getty Manchester United summer transfer targets Gareth Bale - Real Madrid The Real Madrid forward would be a marquee signing, the type that the Manchester United boardroom are keen to make, and The Independent has been told by sources from both United and Madrid that a deal is 'much likelier' than ever before. The player himself though is happy in the Spanish capital. Likelihood: 5/10 Getty Manchester United summer transfer targets Willian - Chelsea Mourinho is a huge admirer of Willian, who he signed in 2013 while at Chelsea. The pair won a Premier League title and League Cup double together the following year and it is believed that the United manager will do his best to sign the player, who has not been a regular starter in Antonio Conte’s system. Whether Chelsea will allow him to leave, particularly to join Mourinho at their rivals is yet to be seen. Likelihood: 4/10 Getty Manchester United summer transfer targets Andrea Belotti - Torino Another of Europe’s most promising players, Belotti is fast becoming well-known after his outstanding performances at Torino, where he has scored 37 goals in 64 appearances since 2015. His best years are still ahead of him aged just 23, which contributes to the incredible €100m release clause, applicable only to clubs outside of Italy, negotiated into his contract. Torino are in no hurry to sell and will drive a hard bargain with any deal likely to start at upwards of £70m. Likelihood: 7/10 Getty

Borussia Dortmund’s desperate need for connections to the elite players who are in Raiola’s client base left them in a weak negotiating position when United bid for Armenian Mkhitaryan, who joined for a fee of £26.3m.