The failed pursuit of Thiago Alcantara was when it all started to go wrong for Manchester United.
They had appeared in pole position to tempt him away from Barcelona by meeting his release clause; until former boss Pep Guardiola surfaced to tempt him away to Bayern Munich.
Any United fans who have watched their side suffer to control the midfield countless times this season, will have sighed when they learned Thiago set two Bundesliga records last weekend for touches in a single game and for accurate passes in a 5-0 win over Eintracht Frankfurt.
But they are not the only ones to rue not having the talented Spaniard in their side.
A club where his absence is being noticed, albeit not at the same scale as United, is his former side Barcelona.
The Catalans did not want to sell him last summer, but had to due to the clause in his contract being met, activated because he had played in under 60 per cent of first team games.
This season they are going through somewhat of a transition under new manager Tata Martino, and a look at the La Liga table would not necessarily cause alarm.
Yet Barcelona are a team just one draw or loss away from a crisis, bearing in mind their incredibly high standards, and a 3-2 loss to Valencia last weekend has stirred up talk.
For the first time in a generation, the problems focus slightly around the central midfield, their traditional area of dominance.
Xavi is claimed to be playing beneath his peak, and Barcelona have little established in reserve to back up himself and Andres Iniesta, with Alex Song never the answer, and Cesc Fabregas preferred in a forward role.
Long-term back-up Sergi Roberto is not deemed ready, the 21-year-old making just one La Liga start all season.
Spanish newspaper journalist Joan Batlle Maria of the Sport publication believes that Thiago would have been invaluable this season.
He wrote: "Selling Thiago broke the natural order of Xavi or Iniesta replacements, forcing call early on Sergi Roberto, younger and less prepared. Maybe now this error is showing."
It's important to consider the context to Barcelona's worries - they sit three points off the top of the La Liga table, recording a total of two losses all season.
Should they lose in the Champions League last 16 to Manchester City however, expect the inquest to begin, and their failure to hold onto Thiago, which dates back to not integrating him enough last season, may well be a central point.
image: © castroquini2011