Lionel Messi
Lionel Messi was left particularly frustrated by Barcelona's 1-0 defeat to Real Sociedad. Reuters

All is not well at Barcelona. An insipid 1-0 defeat to Real Sociedad on Sunday, in which star men Lionel Messi and Neymar both began on the bench, was followed by sporting director Andoni Zubizarreta being given the boot before his assistant, club legend Carles Puyol, soon followed of his own accord. Meanwhile, Messi missed an open training session and was linked with transfers to Premier League giants Chelsea and Manchester City.

Ever since Pep Guardiola’s departure in 2012, and perhaps even before, disharmony has been simmering at the Camp Nou. Now, despite still being able to call upon one of the greatest forward lines ever assembled, sitting second in La Liga and through to the last 16 of the Champions League, the word “crisis” is no longer a hyperbolic reaction. But could it really lead to the greatest player in Barcelona’s history, one who has been with the club since the age of 13, departing?

A gastric problem was cited as the reason for Messi missing training on Monday, although it is widely believed that, despite his later apology to the fans who attended the session, other factors were at play. Guillem Balague’s fine biography of Pep Guardiola discusses the sulks Messi would go into if he was named among the substitutes or was even take off before the end of 90 minutes. Sunday was the first time Messi had not started a Barcelona match this season.

But on this occasion, there appears more to it than a momentary frustration borne out of his love for the game. Catalan publication Sport is among those to have reported that a rift has been brewing between Messi and coach Luis Enrique, with the two said to have had a heated exchange in the run up to a defeat to Real Sociedad that leaves Barcelona a point behind Real Madrid but having played a game more.

Since replacing Gerardo Martino in the summer, Enrique has been unable to return a clear identity to a team that scaled new heights under Guardiola’s four-year reign. Luis Suarez was purchased at great expense during the summer, but the former Liverpool forward has scored just once in La Liga, with Enrique struggling to find a setup that gets the best out of him, Messi and Neymar as well as those behind them.

Away from the pitch things have been even worse. Zubizarreta has paid the price for some questionable transfer business, including one of his final signings Thomas Vermaelen, who arrived injured and will now miss the entirety of the season. Meanwhile, the club is now banned from signing players throughout 2015 after violating FIFA rules about signing international players under the age of 18. Previously, Sandro Rosell resigned as president in the wake of another scandal, this time involving the transfer of Neymar. Messi, too, has had his own problems, and faces a trial for alleged tax evasion.

Could all those factors added up to Messi’s exit? In November, the 27-year-old surprised many by suggesting that such an outcome was a possibility.

“At the moment, I am living in the present,” he told Argentine publication Ole. “I am thinking about having a great year and winning the trophies we want at Barcelona -- nothing else. Later, we will see. In football, things change all the time. Although I have always said I would like to stay there forever, sometimes everything does not always go as you want.”

That scenario remains some way off. It is less than a year since Messi signed a new contract with Barcelona that made him once again the world’s highest-paid player. And, with Enrique’s future in doubt as well as that of much-criticized president Josep Maria Bartomeu, Messi could soon get a landscape at Barcelona that he finds far more appealing.

Even should he not, it will take the biggest transfer in the history of the sport for Messi to leave the Camp Nou in the near future. Messi has a release clause of 250 million euros and it is difficult to envisage Barcelona allowing him to leave for anything less. That, combined with his mammoth salary of 50 million euros a year, means only a precious few clubs can even think about affording the Argentinean.

One of those is Chelsea, who were rather amusingly linked with a transfer on Monday after Messi followed the club on Instagram. Chelsea’s owner, Russian billionaire Roman Abramovich, would surely love a player of Messi’s star power, although it would be fascinating to say the least to see the Barcelona idol playing in a team managed by long time Barcelona-nemesis Jose Mourinho. But then Chelsea already have former Barcelona man and Messi’s good friend, Cesc Fabregas, on their books.

There have also been reports that the Premier League’s richest club could be keeping a close eye on the situation. Manchester City would certainly love the lift to their global brand that Messi’s signing would undoubtedly bring.

Perhaps the only other realistic destination is another club run by Middle East billionaires, Paris Saint-Germain. Just this past weekend, Barcelona-based newspaper Mundo Deportivo reported that PSG had been working for some time to make sure that, if Messi did become available, they would be in a position to sign him and meet Financial Fair Play rules. Keeping in line with FFP will be a huge challenge for any club considering signing Messi. But, while Mundo Deportivo also stated that Messi was committed to Barcelona, his future now appears more in doubt than ever before.