By RORY SMITH

BARCELONA, Spain — It was as they were whiling away one of those long, sultry evenings cooped up in the comfortable surroundings of the Hotel Lucerna in Culiacán, Mexico, that Pep Guardiola outlined to Ángel Morales his vision of the perfect goal.

Over the course of their five months in northwest Mexico, Guardiola, who would become the greatest soccer coach of his generation, and Morales, a journeyman playmaker from Argentina, spent hours together, eating, relaxing, talking. A decade later, though, it is that one thought, that purest distillation of Guardiola’s philosophy, that has stayed with Morales.

“He said that his ideal goal was a move that involved every player on the pitch,” he said. “From the goalkeeper to the striker, everyone would touch the ball once, and then, at the end: goal. I told him it was impossible. I am an Argentinean: I liked to touch the ball three, four times, to dribble past someone. But that was what he said. And then, a few years later, when he was at Barcelona, I saw it come to fruition: football just as Pep had said.”

This is an emotional week for Guardiola. On Wednesday, five months into his tenure as manager of Manchester City, he will return here, to Camp Nou, in the Champions League group stage.

Just as when he brought his Bayern Munich team here, he will be afforded a hero’s welcome. Guardiola will forever be intrinsically linked to Barcelona, to Catalonia. He grew up in Santpedor, a close-knit medieval town up in the hills, a couple of hours north of the city, all terra-cotta houses and unlocked doors. His parents remain there. They speak Catalan, rather than Spanish, as a first language. One of his sisters works for the Catalan regional government.

It was at Barcelona, too, where Guardiola made his name as a player, and where, as a debutant coach, he nurtured one of the greatest teams in history, winning the Champions League twice, the Spanish title three times.

He did it all in Barcelona’s signature style, too, the one he learned as a player under Johan Cruyff and later summarized as: “I take the ball, I give the ball, I take the ball, I give the ball.” Barcelona reveres Guardiola because, by birth and by inclination, he is one of its own.

Yet to view all of his success simply as a product of one institution is unsatisfactory. His influences are far more varied. Before taking charge of Barcelona, he sought out the views of Marcelo Bielsa, the great Argentine coach. He has also sought advice from Ferran Adrià, the chef, among others.

And perhaps most significant: As his playing days were drawing to a close, he made his way to Culiacán, to the Hotel Lucerna, all so he could play for, and pick the brain of, Juan Manuel Lillo, a little-known, much-traveled Spanish coach he had always admired. It is a curious chapter, but a crucial one, in Guardiola’s career. If it was in Barcelona that his ideas were formed, it was in Mexico where they were refined.

“The story of how I met Pep is true,” Lillo said in an interview Sunday. “He had played against my teams before, and then, after a game in 1998 between his Barcelona and my Real Oviedo, my delegate knocked on the door of my office and said Pep would like to introduce himself. Would I see him? How could I say no to a player I liked so much? He said he liked my way of playing, and we talked. We always stayed in touch after that.”

After his time as a player at Barcelona came to an end, and then a spell in Italy, Guardiola moved to Qatar for what many assumed would be the final, lucrative coda to his playing career. He would, though, spend preseason training with Lillo’s teams, maintaining his fitness. The two became so close that Lillo now describes him as “one of the most important people in my life, like a son to me.

“He had always said that the three coaches he liked the most were me, Bielsa and Arsène Wenger,” Lillo, now an assistant at Sevilla, said. Late in 2005, with his friend working in Mexico, Guardiola saw what was probably his last chance to experience playing under one of them.

That year, Lillo had taken charge of Dorados de Sinaloa, an unremarkable team at the wrong end of Mexico’s first division, Liga MX. The club was not a rich one: There were occasional struggles to pay the players, and Lillo had to train his players at a water park.

The city was dangerous, too. Culiacán was in the heartland of territory controlled by Mexico’s most powerful drug-trafficking organization, the Sinaloa cartel, led then by Joaquín Guzmán Loera, better known as El Chapo. Lillo remembered regular reports of “death and murder” and that it was “not a safe place to be.” A few months later, Mexican troops flooded the area, opening another bloody front in the war on drugs.

When Lillo asked Guardiola to sign a short-term contract, though, he accepted, the allure of playing for his friend enough to overcome any doubts.

The adventure ended unhappily — Dorados was relegated, and Guardiola, plagued by injury, made only 10 appearances — but the impression he made was a strong one. “I look at my career and see that there was me before I played with Guardiola and me afterward,” said Marco Mendoza, a Mexican midfielder who played on that team. “Just by playing with him, watching him, listening to him, he made me better. There was so much to learn from him.”

Sebastián Abreu, an experienced Uruguayan striker, recalled Guardiola’s spending hours with him after practice teaching him how to position himself on the field. “I had a way of receiving the ball that he did not like,” Abreu once told ESPN.

“Whenever he saw it, he would say: ‘No, Loco, if you do that, you’re losing three seconds.’ I would say no, until one day he told me we would stay late because ‘if I made a player like Romário do it, I have to do it with you, too.’ In the end, I agreed with him.”

Morales, too, said he believed the Guardiola he encountered in Culiacán was a player in name only. “He was already starting his career as a coach,” he said. Lillo saw it differently. “He played like one of the angels,” he said. “I was so lucky to be able to coach him, even with the injuries. He is the best player I ever worked with. But he was born to coach. It’s just that if you love football, you have to play it first.”

Lillo and Guardiola spoke daily while they were together in Culiacán, the coach said, exchanging and forming ideas. Lillo, modestly, scotched the notion that he could take any credit for the coach Guardiola has become, but it is telling that Guardiola has described the 50-year-old Lillo as his “maestro” and “the best coach I ever had.”

Lillo has fond memories of their time together in Culiacán, that most unlikely crucible of greatness, but they are not of a teacher and a pupil.

“Happiness is not about the place,” he said. “There was not much security there at the time, but we lived a life of work, and of friendship, so those things did not trouble us. I remember those days happily because of the emotions they brought, emotions that endure now, that will last all our lives.”

It is enough to call Guardiola a friend; he does not need to believe it was in Culiacán that he grew into the coach he would become. After all, as Lillo said, “a maestro does not need a maestro of his own.”