Manchester United began to seriously consider luring Paul Pogba back to Old Trafford within 12 months of his exit.
United have paid a world-record £89m to sign the 23-year-old, four years after he left to join Juventus for £1.5m.
Sir Alex Ferguson was not on good terms with Pogba’s agent Mino Raiola and could not get him to sign a new deal.
It is understood the first attempts to repair the relationship between United and Raiola were made in the months after Ferguson retired in 2013.
Executive vice-chairman Ed Woodward, who took over the day-to-day running of the club from David Gill in 2013, arranged a meeting with Raiola.
Knowing Pogba had left on good terms, United monitored the player on a regular basis from that time and noted his progression with the Turin club.
According to senior club sources, United did not make a move for the France midfielder until two months ago.
Real Madrid are believed to have remained keen on Pogba until the transfer was completed, when the player described his return to the club as like “coming back from a holiday”.
In addition to the transfer fee, United are also committed to make a further £4.25m payment to Juventus should Pogba sign a contract extension.
The club are paying Raiola for his part in the deal but they are not making an additional payment to the agent on behalf of Juventus, who have made a payment out of the fee they have received from Old Trafford.
Four in, how many out?
Manchester United paid Bayern Munich £14.4m for Bastian Schweinsteiger in 2014
Having secured his four “fundamental” transfer targets of Pogba, striker Zlatan Ibrahimovic, playmaker Henrikh Mkhitaryan and defender Eric Bailly, United manager Jose Mourinho has the 23 outfield players he feels are required for a season that involves a Europa League campaign.
There are bound to be departures though, with the Portuguese known to dislike bloated squads.
Mourinho has already said German Bastian Schweinsteiger does not figure in his plans, 12 months after the midfielder completed a high-profile move from Bayern Munich.
It is understood there has been significant interest in Schweinsteiger from clubs at home and abroad, and despite the 32-year-old being at the top end of United’s pay scale, it is not thought his salary will prevent his exit before the 31 August transfer deadline.
Another player with no immediate future under Mourinho is Adnan Januzaj.
Former United manager David Moyes has expressed an interest in taking the Belgium winger to Sunderland.
The 21-year-old, whose contract runs to 2018, is likely to leave on loan rather than in a permanent transfer.