Pep Guardiola secretly signed his first contract with Manchester City four months before the official deal was announced, a new report alleges.

In the third of a four-part expose on City by the Football Leaks whistle-blowers, the report in Der Spiegel explains the exact date Guardiola agreed his move.

It claimed Guardiola had already secured a deal with City just two months into his final season with Bayern Munich, signing a contract on October 10, 2015.

The documents, obtained by Der Spiegel, say the Spaniard was guaranteed a payment of £13.5million in his first season with City, and £16.75m in the second.

The announcement was then made public on February 1, with then-boss Manuel Pellegrini revealing he would leave the club when his contract expired on June 30, but interestingly City had previously refuted claims the deal was done.

Several weeks after the deal was signed, it was reported that the club’s director of football Txiki Begiristain had met Guardiola in Barcelona, with talks over a potential deal progressing.

Der Spiegel claimed that, although the story was untrue because Guardiola’s contract was already signed, City were desperate to quell the speculation and moved to get the story removed.

In an allegedly leaked email between club officials, it is claimed team spokesman Simon Heggie wrote: ‘I’ll call him and tell him we want it removed,’ before later noting: ‘I’ll send a note around to other media to tell them to ignore it.’

It is claimed that City were keen to control the announcement of their new boss, deciding exactly when to reveal Guardiola without the media taking over.

The latest allegations against Manchester City are the third part of a four-day expose by the Football Leaks whistle-blowers, in the pages of German paper Der Spiegel.

The investigation began on Monday with allegedly hacked documents which claimed owner Sheik Mansour paid large chunks of sponsor deals himself so the club could avoid significant Financial Fair Play penalties.

In one agreement with Etihad Airways, it is claimed a staggering £59.5million of the £67.5m was essentially financed by Mansour.

The revelations could lead to sanctions from UEFA and the Premier League. Neither would comment when asked earlier this week and there is concern about the method by which the documents were obtained.

If they conclude that the emails have been obtained illegally, City — who were sanctioned in 2014 for a breach of FFP rules — could face no further action.

City reiterated earlier this week that they ‘will not be providing any comment on out of context materials purportedly hacked or stolen from City Football Group and Man City personnel and associated people’.

Day two of the investigation divulged details on an alleged secret project called ‘Longbow’, created to shift the cost of player image rights to a third-party.

Football clubs are obliged to pay their athletes for the right to use their image, be it in posters in the club shop or advertising for new shirts, but it is alleged that Manchester City farmed out the rights in a bid to save spending costs.

It is claimed that a marketing company called ‘Fordham Sports Management’, allegedly steered by Jonathan Rowland and his father David, bought the image rights, but were secretly fed £11million a year by Man City’s owner Sheik Mansour.

It has been reported, therefore, that the deal was in fact a ‘closed payment loop’, in which Mansour’s holding company Abu Dhabi United Group (ADUG) transferred money to the Rowlands for the purchase of the image rights of their players, which then allowed Manchester City to hide the expenditure.

When Blackfish Capital – the Rowlands’ private investment firm – was called to shed more light on the issue, the request for comment was declined. There is no indication that ‘Project Longbow’ is illegal.

In an unrelated set of allegedly leaked emails, it is also claimed that Manchester City CEO Ferran Soriano was aware of the scrutiny that the club could be under in their fight against Financial Fair Play.

In memos claimed to have been seen by Football Leaks whistle-blowers, they say Soriano – reporting back to club executives after a meeting of the European Club Association (ECA) – wrote in 2012: ‘They are all pushing for FFP in a way that would ashame (sic) any industry association.

‘We will need to fight this [FFP regulations] and do it in a way that is not visible, or we will be pointed out as the global enemies of football.’

Key players in the whole scandal are:

Sheik Mansour (Mansour bin Zayed Al Nahyan) who is the Owner of City Football Group, which consists of Manchester City, Melbourne City and New York City Football Clubs. A member of the royal family of Abu Dhabi, he is current Deputy Prime Minister of the United Arab Emirates and also Minister of Presidential Affairs.

Khaldoon Al Mubarak who is the Chairman of City Football Group, and also the chief executive officer and managing director of Mubadala Development Company. He was first appointed Chairman of the Board of Directors by Mansour after his takeover in September 2008, before becoming the chairman in 2013.

Ferran Soriano: Ferran first delved into the world of football with his boyhood club Barcelona, first as Economy Vice President and then interim CEO while Pep Guardiola was the manager. In September 2012, he was appointed CEO of Manchester City and in 2014 added the CEO roles of New York City and Melbourne City to his job-list.

Simon Pearce: An Australian member of the City Football Group board who is widely considered to be one of the UAE’s most influential officials and is a close ally of Khaldoon. He was appointed to the board when Mansour’s takeover was completed in 2008, and is credited by the WSJ as helping ‘smooth’ the process.

The Rowlands: Jonathan Rowland and his father David are the experts the club allegedly brought in. David was in the news previously when he donated millions to the Conservative Party, before being appointed treasurer, a post he never actually took up. In the late 1980s, he also helped fund a takeover of ‘Edinburgh Hibernian’, parent of Hibs Football Club. The deal then turned sour when the company went into receivership, and he was attacked in the Commons and labelled a ‘shady financier’.