His is a very different kind of madness from that which saw Paul Gascoigne ordering pint mugs of espresso to prove to his Lazio team-mates that the little cups they used were, well, a bit cissy – he passed out from caffeine poisoning, naturally. It is the madness that comes with being completely apart and alone, usually in Bielsa's case with a stack of football videos for company.
And yet, should Pep Guardiola be foolish enough to exchange the Nou Camp for the regime run by Roman Abramovich at Stamford Bridge, this lawyer with his glasses hung round his neck, like Larry Grayson in a tracksuit, is probably the best bet to succeed him as manager of Barcelona.
He will have the support of Guardiola, who reportedly once drove through the night to question him on the principles of coaching, and he has already been given the backing of perhaps the most influential figure at the Nou Camp, Lionel Messi.
Messi, like Bielsa, is from Rosario, the third city of Argentina, which dominates its vast agricultural interior. Agricultural regions are rarely hotbeds of revolution – there have been very few red flags fluttering over Taunton – but Rosario was different in the days when it was in a ferment of Peronism, Argentina's strange mixture of union power, working-class rhetoric and right-wing posturing, glamourised forever by the musical Evita.
By the time the young Marcelo Bielsa was disobeying his father and not just supporting but starting to play for Rosario's main club, Newell's Old Boys, at left-back, the army decided it had endured enough of this and put its tanks on to the streets of Buenos Aires. Unlike the Peronists, the junta knew exactly what they stood for. To a man, they were card-carrying fascists.
Sir Alex Ferguson dates his confirmation as a socialist to the days when he visited his mother, dying of cancer in Glasgow's Southern General, and was appalled by the hospital's rotting, neglected state. For Bielsa, it was probably the moment his elder brother, Rafael, "disappeared".
Rafael Bielsa ended up in El Castillo, one of the junta's most notorious torture centres. Given that Argentina's Premier League has just been renamed after the sunken cruiser General Belgrano, it is worth pointing out that the navy provided most of the torturers. Eventually, Rafael was exiled to Spain.
Like Martin O'Neill, whom he resembles when prowling the touchline, Marcelo Bielsa studied law. The other dictatorship Bielsa has always fought against is what he calls "the dictatorship of results", a regime that has Chelsea by the throat. After a knee injury forced him out of playing, he became obsessed with tactics and the need to win well. His signature formation is a 3-1-3-3 designed to press teams hard.
In the November rain, at Bilbao's soon-to-be demolished San Mames, they met Barcelona full on. "They came at us like beasts," said Guardiola afterwards. "I have never played a team that were so aggressive and who denied us so much space." Appropriately – given that the Basques call the San Mames "The Cathedral" – Guardiola called it a "hymn to football". It finished 2-2.
Bielsa's search for perfection reached its peak when he was made manager of Argentina. It was 2002 and the air must have tasted very sweet for him and his persecuted family. The army was gone, the Peronists were back, his sister, Maria, was on her way to being vice-governor of Santa Fe, the province that contains Rosario, while Rafael was a few months away from being appointed Argentina's foreign secretary.
Marcelo would be radical, refusing to pair Gabriel Batistuta and Hernan Crespo as the media demanded and falling out with Javier Saviola. They did pass beautifully but, like one of Arsène Wenger's recurring nightmares, the passes never seemed to threaten a goal. Far from winning the 2002 World Cup, Argentina did not even make it out of their group and in Sapporo lost to England and a penalty from David Beckham, providing his one concrete contribution to a major tournament.
It should have cost Bielsa his job, especially since the World Cup was won by Brazil, but he survived, putting his faith in young talent like Javier Mascherano and the urchin from the tower blocks of Fuerte Apache, Carlos Tevez, and took Argentina to the gold medal at the Athens Olympics. Then he walked away, just as he was to walk away from Chile after taking them to the second round of the 2010 World Cup. He cited the politicking at the Chilean FA but it appears that with Argentina he was mentally exhausted.
He re-emerged to take charge of Chile, who aside from hosting the World Cup in 1962 had made little impact in South American football. The qualification campaign was a series of fluid performances and jaw-dropping results that culminated in a 1-0 defeat of Argentina in Santiago that cost Bielsa's successor as national manager, Alfio Basile, his job and ushered in the brief, chaotic reign of Diego Maradona. He returned from the South African World Cup a hero, but not in his own land.
Athletic Bilbao was a strange choice. Founded by shipyard workers from Sunderland, it has a tradition of powerful, direct football, epitomised by its centre-forward, Fernando Llorente, a kind of Spanish Shearer. It has only ever signed Basques, which limits its transfer targets and makes them prohibitively expensive. Sometimes, it has resembled Yorkshire cricket in the 1970s; suffocated by tradition and by-passed by events.
He began, naturally, with instant revolution, changing Bilbao's style of play and the positions of their players. If you wondered why Guardiola used Mascherano as a centre-half after signing him from Liverpool, it was from Bielsa's theory that midfielders in defence can launch counter-attacks more quickly.
Just as Brian Clough turned Kenny Burns from a striker to a defender when winning the championship with Nottingham Forest in 1978, so Bilbao's players have had to get used to different views. It came at a price. This season Bilbao made their worst start in a decade before recovering to become the most credible candidates to fill La Liga's fourth and final Champions League position and making the final of the Copa del Rey, which at the San Mames is probably the limit of their realistic ambitions.
Before the recovery, there was a revolt of sorts with the squad demanding a return to the traditional flat back four. Bielsa asked them to put it to a vote. They voted for the back four, their manager told them they would be employing three at the back. He may come from a family of politicians but Bielsa extends democracy only so far.
