Manchester United's Anthony Martial
Given their current positions in the Premier League, it would hardly be a surprise if Tottenham's reported interest in Manchester United's Anthony Martial (via Daily Mirror) comes to nothing during the summer.
However, perhaps a transfer that took place in 2015 involving Jose Mourinho should give Spurs some hope that the current United boss would give a potential deal his blessing, even if it means that one of their main rivals strengthen their ranks at their expense.
Martial has struggled to make a major impression since the Portuguese's arrival at Old Trafford, having only started 10 games in the top flight this term, and having only played one full game in the league all year.
That kind of involvement would suggest that United would consider letting him go if they received a substantial offer from another club. Whether Tottenham have the desire to break the bank to sign him - United signed him for an initial £36 million (via Mirror) - remains to be seen, but it would not be a shock if the Red Devils board were incredibly reluctant about letting him move to White Hart Lane.
Manchester United's Juan Mata with manager Jose Mourinho after he has been substituted
Mata had won the Blues' player of the season award in both of his full seasons at Stamford Bridge, but Mourinho's return to the club saw the Spaniard take on a much more peripheral role, much like what Martial has had to settle for following Louis van Gaal's departure as manager last summer.
On that occasion, Mourinho appeared to have few qualms about leaving the path clear for Mata to join United, who, despite languishing under David Moyes, clearly had the resources to potentially get themselves back into the title picture where they would be back competing with the likes of Chelsea.
Tottenham manager Mauricio Pochettino
That deal would perhaps hint that if Mourinho was given complete control over Martial's future and was willing to let him leave, he may not be overly concerned about the idea of letting him leave for a direct rival if the other aspects of the deal benefited United.
So if Mourinho does view Martial as as important to his United side as he deemed Mata to be to his Chelsea team previously, then perhaps the door could be open for Tottenham to pull off the stunning move if the board are willing to make the kind of offer that forces United to sit up and take notice.