A decade ago, FC Barcelona seemed like the model club. Under Pep Guardiola, redefining how football could be played, it was about to win its third straight league title and its second Champions League title in three years. Others sought to copy its success. Yet now it faces financial meltdown, with its greatest player ever on the brink of departure and several directors battling allegations of corruption. Amid the crisis with the future of the club at stake, it has turned once again to the controversial figure whose presidency set it on the way to that last period of sustained success.