The Catalans were unable to find a reaction after they were knocked out of the Champions League on Wednesday and are paying the price for years of dubious decision-making.
Injuries in defense meant Barca began with Jose Pinto, Martin Montoya, Sergio Busquets, Javier Mascherano and Adriano at the back. Two midfielders, a ultility man and a second-choice right back. And to make matters worse, the hapless Alex Song was picked to play in front of them. It was, quite literally, a disaster waiting to happen.
So when Granada scored, there was an air of inevitability about the way it occurred. Song was pressured into conceding possession, Busquets lost his marker and Montoya couldn't cover in time to stop Yacine Brahimi from firing past Pinto. A comedy of errors, yet nobody at Barca was laughing.
Granada, wearing red and white like Atletico, appeared to have learned lessons from Simeone's side as the club played narrow and squeezed space to prevent Barca from playing its natural game. In truth, that was made easier anyway by the presence of Song, never good enough to be a midfielder nor a defender at the Catalan club.
Barca's best chance of the night fell to Busquets in a penalty-box scramble in the second half. Which said it all, really. In the meantime, Granada contrived to miss two one-on-one opportunities and saw a decent appeal for a spot kick waved away as well. All that with only 14 percent possession.
Martino's changes failed to ignite the Catalans, with Jordi Alba for Adriano a bizarre substitution and Alexis Sanchez in place of Busquets baffling, too. Song, somehow, stayed on and ended up in a patched-up partnership alongside Mascherano.
Tata takes his share of the blame for the performance and the strange selection, but what of Barca's sporting director Andoni Zubizarreta? In the post since the summer of 2010, he has failed to address the Catalans' pressing problems in central defense and the fact that Barca ended up with Song and Mascherano at the back on Saturday is a damning indictment of the Basque's tenure.
Everywhere you look this term, from the boardroom to the pitch itself, this club continues to fall into decay and decadence - and this damaging defeat leaves Barca's hopes of winning La Liga now hanging in the balance as Atletico can further extend its advantage on Sunday, while the Champions League is already gone and back-to-back losses this week is surely the worst way possible to prepare for Wednesday's Copa del Rey final against fierce rival Real Madrid, which now assumes even greater significance.
Martino is accused of never fully understanding this club and evidence seems to suggest that may well be the case. Tata's decision to stick with what he had in the summer and not bring in anyone after Neymar's arrival already looks ill-fated and misguided, when a central striker to replace the outgoing David Villa, a defender and even a goalkeeper to learn under the wing of Victor Valdes would all have been shrewd signings. Much of that, though, is also down to Zubizarreta's failure to address the imbalance in this squad and Barca is now paying the price for years of mismanagement - just when the titles are being handed out.
End of a cycle? Suddenly, it's starting to look like it.
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