Marcelo Bielsa's is best known as ''El Loco'' - The Crazy One - and his team Athletic Bilbao embraced their new coach's nickname to appoint him.
Despite his maverick tactics and colorful personality, Bielsa is also rated among the top coaches in the world.
Led by that reputation and perhaps the most promising core of young talent since its last Spanish league trophy in 1984, club members couldn't resist the chance to match Bielsa with their team as they dumped coach Joaquin Caparros despite the club's impressive sixth-place finish last season.
Bielsa didn't take long to make an impression. He walked round the training field hand-in-hand with a youngster who had asked him for an autograph after his official presentation.
''Without doubt, he's got his own style,'' Athletic midfielder Markel Susaeta said.
Those unorthodox ways have brought success in prior stints with Argentina, Chile and Newell's Old Boys, and Bielsa has quickly set about raising expectations at Athletic.
''I don't understand why we can't go to the Bernebeu and win against Real Madrid,'' the Argentine coach said of his team's season opener on Saturday.
Bielsa cultivates a detached air at public appearances and on the training field, peering over glasses worn low on his nose or hanging around his neck as he answers questions or oversees practice sessions.
He has been known to engage in tactical discussions at news conferences that can go on for hours and seldom shows emotion off the pitch - even when his team wins.
During matches, however, it's easy to see where he gets his nickname.
When Athletic played lower-league side Alzira in his first preseason friendly, Bielsa's idiosyncrasies showed as he screamed and waved his hands before calming down.
For Athletic midfielder Javi Martinez, the surprises cane be boiled down to the smallest details.
''I think it's the first time since I've been playing in the first team that a coach has had me take a throw-in,'' Martinez said after an early session.
On paper, Bielsa and Bilbao look like a good fit. The Argentine coach is revered for his obsessive attention to detail and encyclopedic football knowledge - both bordering on manic - but the Basque club has its peculiarities, too.
The club only fields players with links to the Basque country and is one of four clubs in Spain to be owned by its members. Despite that, Athletic form a select group with Barcelona and Real Madrid as the only three clubs never to be relegated from the top division.
Expectations are high in the Basque coastal city with World Cup winners Fernando Llorente and Martinez and Under-21 talents Iker Muniain and Ander Herrera providing offensive-minded players.
It was an agreement to install Bielsa as coach that swept former Athletic player Josu Urrutia to the club presidency in June because the Argentine has a reputation of taking unfancied teams to the top. His three Argentine championships in the 1990s were won not with traditional powerhouses Boca Juniors or River Plate, but with Newell's Old Boys and Velez Sarsfield.
His six years as Argentina coach brought mixed success, but it was his time in charge of the Chile that secured his reputation as he is credited with reviving the national team's fortunes by masterminding its progress to a first World Cup in 12 years in South Africa. There, Chile trained under a torn flag reputedly rescued from a building that had collapsed during the earthquake and tsunami that killed more than 500 people and left 200,000 homeless earlier that year.
That use of identity as motivation could help in Bilbao with its proud Basque heritage.
Bielsa acknowledged that Athletic's ideals appealed to him.
''The sense of belonging, identification and representation - that's all very nice for a coach because there is a zone of stimulus beyond the professional motivations of money and recognition,'' he said.
Bielsa is also keen on hard work. The Athletic players have had only a couple of days off since returning from vacation.
''Everyone has told me that we are going to learn a lot, but that we are also going to suffer, although later we will have time for enjoyment,'' Herrera said.
Martinez, Herrera, Muniain and Mikel San Jose were all part of the Under-21 European Championship-winning squad in June, while Jon Aurtenetxe and Jonas Ramalho were part of the Spain Under-19 team that became European champion at the beginning of August.
A continuing flow of talent from the youth squad will be important as Bielsa is unlikely to have much money to spend as he tries to improve last term's finish and qualify the club for the Champions League for the first time since 1998-99.
That doesn't seem to worry Bielsa.
''What happened before does not always give you authority to predict the future,'' Bielsa said.
