An innovator and lateral thinker rewriting the coaching manual
Bayern Munich became winter champions of Germany for the third time under Pep Guardiola a week ahead of the December break thanks to a novel device in their head coach's encyclopaedia of management techniques.
They had been struggling to overcome Ingolstadt at home, when, coming up to an hour into an attritional Bavarian derby, Guardiola handed his captain Philipp Lahm a piece of paper.
Lahm studied it with the kind of urgency you might give a ransom demand. He beckoned team-mate Javi Martinez to have a read. Striker Thomas Muller and defenders Holger Badstuber and Rafinha were also appraised and each of them took up a fresh position on the pitch.
Two goals and 15 minutes later, Bayern had interpreted their manager's Da Vinci Code perfectly and wrapped up their 14th win of the Bundesliga season.
Why the written instruction? "I needed to switch four players around, and rather than point out instructions to them one by one," Guardiola explained, "better they communicate with each other."
Guardiola had decided on the adaptations within a seven-minute period between making a substitution, and briefing the incoming Thiago Alcantara on what he wanted from him and from where, and then sketching out yet another new formation.
His players were surprised only that the rethink reached them via hieroglyphics.
At Bayern, the idea of perpetual, fluid tactical evolution is part of the match-day experience under a studious coach whose attention to detail, whose proactive lateral thinking has made him more admired than probably any contemporary in his profession.
As an innovator, Guardiola has stimulated his club and most of the Bundesliga, even if the 17 others who share the top division with Bayern seem ever further behind in the Bavarians' rear-view mirror.
But there are aspects of Guardiola's intense approach that will not be missed by some of the executives at Bayern.
They were always aware, even when they celebrated the coup of appointing him in 2013, that the restlessness that drives his search for the best game-plan, minute by minute, for every contest, is matched by a restlessness that seems part of his career design.
Guardiola, 44, has never been sacked from a senior coaching job. He left Barcelona after four years of his own volition, resisted extravagant offers to follow his epoch-defining achievements at Camp Nou with an immediate move and instead took a 12-month sabbatical.
Arriving at Bayern, where it is his choice to leave next May, he had it in mind that three years in the Bundesliga would likely bring him to another point where he felt ready for something else.
"Winning is tiring when you're continually testing yourself against your own standards," Guardiola's friend and fellow Spanish coach Michel said of him.
"His goals have had to be set around maintaining the motivations of people who might, because they are only human, start getting less excited by success."
The majority of Bayern's players are showing palpable development under his watch.
The list of young footballers whose value has grown thanks to Guardiola's guiding them to discover greater versatility and nous in themselves is extensive. Some would be tempted to following him, their guru, if he asked them to come to his next club.
Bayern's next coach, Carlo Ancelotti, whose appointment has been confirmed six months in advance, needed assurances the best players would still be there when he takes over in June.
That is why Bayern extended the contracts of Muller, Martinez and Jerome Boateng last week.