Lionel Messi exit the aftermath of Barcelona embarrassment

It was the result that stunned the football world on Tuesday evening as Paris Saint-Germain stormed to a 4-0 victory at the Parc des Princes against Barcelona in the UEFA Champions League. Despite the presence of their celebrated forward trio of Messi, Suarez and Neymar, Luis Enrique's side were comprehensively humbled on a Valentine's night to forget in the city of love.

But while Enrique and his backroom staff look to do the unprecedented and reverse a four-goal defeat in the competition, the impact of the result could dictate the future direction of the club and its current generation of players.

Barcelona were well-beaten by a well-organised and well-calculated plan by PSG boss Unai Emery, a man not unfamiliar with the traditional ways of the Catalan giants after making his name in Spain with Sevilla. In recent years Barcelona have been saved from embarrassment by their forward line, but the side have become easier to expose under the guidance of under-pressure boss Luis Enrique, and change at the top became all the more inevitable after the defeat.

There is no doubt that the opinion and happiness of Lionel Messi carries significant power within the confines of the Camp Nou, but the diminutive genius turns 30 later this year, and he will not accept wasting any of his playing time performing for a club in obvious transition, as he enters the final few years of his incredible career. Pep Guardiola's managerial credentials were shaped by the brilliance of Messi, and speculation has always surrounded a reunion between the two football heavyweights before the Argentinian superstar calls time on his playing days.

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It has always been widely believed that Manchester City's wealth, combined with the appointment of Guardiola, would eventually attract Messi to the Premier League. But the beauty of football is built upon its surprising twists, and it may yet be the demise of Barcelona as a European superpower that forces Messi to seek glory elsewhere. His finest hours in the colours of the club he loves came under the management of Guardiola, and the opportunity to reunite may prove to be far too tempting as Barcelona look destined to finally enter a time of significant transition.

Losing Messi would be a devastating blow for the club as a whole, and while he may only have a few more years left at his very best, for him not to see them out in the colours of Barcelona would be unforgivable in the eyes of the millions of fans that worship him around the world. No influential figure within the Barcelona hierarchy would wish to be tainted as having been involved in his departure, but there are clear signs that the club have a long road back to finding the brilliance that defined a generation, and the rebuilding process will take a significant amount of time.

However, defeat to PSG was just one night, one bad night at the office, against a talented side managed by a man with a hugely impressive record in European competition. Barcelona remain a star-studded side on paper, and while Luis Enrique is now highly unlikely to be the man responsible for bringing back the principles and philosophies that generated so much success in recent years, there are few managers capable of reversing a concerning trajectory that has seen the club become a shadow of former greatness.

Messi has no time to waste being a part of a rebuilding project as he enters a period in his career when he needs to be at a club moving in the right direction at the very least, and his influence on Manchester City at this stage of their evolution under Guardiola looks increasingly like the perfect match.

Of course, taking Messi away from Barcelona would take significant work and serious investment, but if any manager can sell him a footballing dream, it is Pep. However, there are other issues to consider, and the private luxury lifestyle that Messi and his family enjoy will be compromised by a move abroad. It is not something that his nature suggests would be of little concern, while his burning passion for Barcelona and the part they have played in making him one of the greatest players of all time cannot be forgotten as they enter this time of transition.

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But there are other elements that could force a move, and the reported unrest of Sergio Aguero to Guardiola's preferred system and his role within it could prove to be a key bargaining tool. Both Aguero and Messi are world class players, and a switch between the two makes the possibility of a deal all the more real. Barcelona will always be a key part of Lionel Messi's career and his life, but he has more than repaid the faith shown in him during his formative years.

If he is to end his career at the very top, then there is a manager currently overseeing a long-term project that is perfectly suited to his remaining ambitions. It would be the transfer story of a generation, and it is far from unthinkable at the present time.