The King is dead. Long live the King. As we pour over in great detail about the myriad of reasons behind Barcelona's Champions League exit at the hands of Chelsea, one thing has become abundantly clear - they lack a plan B. So is this the end of the Barcelona as we know it? Or is it simply just the dawning of a new era?

Barcelona have been a complete powerhouse in terms of both domination, success and substance the past three years, but as the excellent Jonathan Wilson recently pointed out, even the very best teams of their eras only tend to rule in three-year cycles. Barcelona have fallen foul of this one golden rule, a truism which lasts the ages.

So where has it all gone wrong this season for Barcelona? The league chase, and it was for the most part it was a chase, was undone by some indifferent away form earlier on in the season which immediately put them on the back foot. Most have pointed out the fact that Barca had their least intensive pre-season in recent memory this summer too, as they whored themselves around the US. By choosing to place commercial interests before footballing ones, they've ultimately paid the price as the season has entered its final and most crucial phase and they looked decidedly not only shorn of ideas against both Chelsea and Real Madrid, but of puff also.

Moving onto the pitch, this season has seen manager Pep Guardiola experiment with his tried and tested 4-3-3 formation and over recent months, in the big games in particular, has come to rely on a 3-4-3 formation, with Mascherano dropping back into a centre-back role and Alexis Sanchez leading the line with Lionel Messi dropping off him as a false nine, breaking from deep.

This change has hit Barcelona hard in two ways. Firstly, they've lost a lot of fluidity and pace to their passing game. Far too often now, they've struggled against lowlier opposition which have been willing to sit back and soak up pressure. They've struggled to carve open teams on the break with the regularity that they used to. In short, they're simply not moving the ball as quickly now.

Secondly, the change in formation now means that they lack a focal point to their attack. I still maintain that the best Barcelona side, collectively, that I have seen is the 2008/9 vintage, with Samuel Eto'o leading the line from the front. It offered them a different, more direct dimension to their game and they always had a 'get-out' ball if they needed to chase a result.

The 3-4-3 formation has worked in patches, but it heaps far too much creative responsibility onto Lionel Messi, who has, to put it politely, carried this team for months now, so his lacklustre displays in the recent run of fixtures is somewhat understandable.

The formation works on the understanding that goals come from a number of different positions, but at key junctures in the season, aside from Messi, Alexis Sanchez and at a stretch, Xavi, few others have stepped up to the plate and played their part.

Pedro for instance, an integral cog in the Barcelona machine these part two years or so has just three league goals this season compared to 13 in 10/11 and 12 in 09/10. David Villa managed to bag 18 goals last term, but has just five in the league this campaign, after being ruled out for the remainder of the season with a broken leg in December. Andres Iniesta struck eight times last season but has scored just twice this year  and while Cesc Fabregas has contributed nine goals in the league, he has faded terribly since the turn of the year as he gets to grips with a more tactical, patient approach to the game at his new/old club.

A lot of emphasis in the aftermath of the two results against Chelsea has been placed on the absence of Villa, perhaps too much in my eyes. Whether Guardiola would have pursued with the 3-4-3 so vigorously had the Spanish international not been ruled out through injury for the rest of the season, we will never know, but to say certain results this season would have been different had he been present is a lesson in futility if ever there was one.

Lest we forget, before we conveniently gloss over the facts in the pursuit of an excuse, Villa was starting to be marginalised to an extent prior to his injury. Rumours of a bust-up with both Guardiola and Messi refused to go away and he simply wasn't the nailed on starter he'd been the previous season.

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What Barcelona do unquestionably miss in his absence, though, is that directness. Villa is not on a par with Eto'o in that regard, but he has not been raised and indoctrinated into the Barca way, and as such, he isn't afraid to have a pop from outside the box from time to time. Against Chelsea, aswell as the fluidity and pace to their play that was missing, Barcelona could also often been found guilty of trying to pass the ball into the net, which is somewhat reminiscent of Arsenal a few years back. In essence, they gave into the worst excesses of tiki-taka; passing for passing's sake, with no penetration in sight.

That is not to say that this Barcelona side is beyond repair, far from it. They are still quite simply a juggernaut of European football, but they've been overworked and fell short of their best form at a crucial time in the season. However, the club require at least two significant signings in the summer, for the current squad is unbalanced in key areas.

The story that the club have prioritised Gareth Bale as the club's top transfer target in the summer is both intriguing and wholly understandable. Bale's directness and pace could add something extra to the side as they seek a long-term replacement for Eric Abidal, although I would argue that they require reinforcements elsewhere first.

Carles Puyol has creaked terribly these last few months, and while the thought of the club purchasing a recognised and specialised centre-back may be nothing short of blasphemous, Thiago Silva and Nicolas N'Koulou have been mooted as targets for a reason and to put it quite frankly, they need to add some height and strength to their side, particularly at the back. Guardiola has been short of cover at the back ever since he was forced to sell Dmytro Chygrynskiy back to Shakhtar Donetsk at a huge loss to help pay off some of the club's sizeable debt in 2010 and it's an area that requires addressing.

Up front too, they require an out-and-out centre forward of genuine class, but one that's prepared not to be involved every game of the season. Both Fernando Llorente and Edinson Cavani would fit into Barca's pressing style off the ball, much more so than Zlatan Ibrahmovic did and the clinical but lazy Falcao ever could. The sight of Seydou Keita coming on as a make-shift striker in the closing stages against Chelsea tells you that Guardiola is probably as aware as anyone of his team's shortcomings in this area now.

Prophecies of their demise have been laughably premature. The pedestal that we all placed them on has almost gleefully been knocked out from underneath them by some with proclomations that Barcelona were never really that good after all, that it was all the Emperor's New Clothes and that they'd all seen this day coming a mile off. It's all complete and utter poppycock of course, but that won't stop the hypocrisy of some.

Barcelona are still the team of our times, after all, Jose Mourinho isn't known to deal in prolonged spells of brilliance, rather short staccato-like periods of all out Blitzkrieg. Perhaps Guardiola tampered and tinkered with something which didn't need fixing all that much in the first place in the pursuit of more flexibility, but the fact that this Barcelona side is constantly evolving is a positive thing rather than a stick that can be used to beat it with. The Barcelona you see this season is not the same as last season, and it most certainly won't be the same as next year. A terrifying prospect.

Nevertheless, with a couple of key signings in central positions next season, Barcelona will still be somewhere close to the force that we've all come to recognise, and losing out on retaining both the league and Champions League titles inside a week will have hurt them dreadfully. They now have the hunger back, something to aim for and they are no longer the ones people are looking to knock down and depose, they are the leaders of the chasing pack, and that is an ominous thought for Jose Mourinho's Real Madrid before he even contemplates resting on his laurels in the summer, content that the last Clasico helped deliver a knockout blow.

You can follow me on Twitter @JamesMcManus1

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