There is a special day in the Guardiola household.

"Valentina was born on the 6th of May [in 2008], it was also the day we played against Huddersfield to lift the title," Pep Guardiola tells Goal, converging two of the proudest moments of his life.

This year, as he sat surrounded by family and his triumphant Manchester City players at a huge end-of-season party, with Valentina, on her 10th birthday, fast asleep on his lap, Guardiola cast his mind back to yet another significant milestone in his life.

"The day that Valentina was born, Joan Laporta came with my friend to the hospital and told me, 'You will be the next manager of Barcelona'."

The Catalan had been in charge of Barcelona Atletic - the club’s 'B' team - for less than a full season when he was told that he would be taking over the senior side.

The idea was actually first put to him over lunch at the Hotel Roma, just a block from La Rambla, a few months earlier.

"You do not have the balls," he told Laporta.

The president was serious: "If you have the balls, you will be the next manager of Barcelona."

"It was a very good year, very hard," Domenec Torrent, whose knowledge of the Spanish lower leagues was vital to Guardiola in that year at Barca B, tells Goal. "It was Pep’s first year as a coach, he had to keep learning game by game.

"The Spanish Tercera Division is very, very hard," he continued. "There are a lot of veteran players and we had very young lads, but they were like sponges, they learned everything so fast.

"In the second part of the league they started winning games more impressively, far better than the first, because they learned Pep’s concepts better. The only way to learn was to keep playing, it was like a Masters degree for Pep."

Guardiola agrees: "Definitely. Definitely, it was so good for me. It was good because I had one game a week, I had time to analyse my process, and I did not have spotlights, I did not have media.

"I completely agree with Dome, it was the best school. First of all because I was a virgin! Dome helped me a lot because he was a manager in that division, the fourth division, for many, many years, he knew exactly the pitches, the stadiums… not stadiums, because there are no stadiums. You can imagine in England in League Two or the Conference, it is quite similar."

This is where Guardiola began his coaching career. Six years after leaving Camp Nou as a player under something of a cloud, he returned as coach of Barca B on the back of their relegation to the Tercera Division, the fourth tier of Spanish football

"When Pep arrived I had already had two years in the youth teams and my plan was to leave, but I had a conversation with him and he convinced me to stay," says Marc Valiente, the captain of the side.

"What I remember most was he said that because we had just been relegated, we had the obligation to get promoted again, because Barcelona do not belong in the fourth tier."

Guardiola had told his players that they had to do better and he immediately set about raising standards; he brought in Torrent - who only recently left Pep to take charge of New York City FC - and Carles Planchart, who still works with him to this day, to analyse the opposition.

This was "brand new" for the team and Victor Sanchez, the current Espanyol midfielder, adds: "We did not so much look at what the opposition did but what we could do to get the advantage over them. The videos were always focused on what we had done badly, on why we could not find a breakthrough, either because of mistakes in attack or because we had not played out from the back well enough, but always focused on trying to get the better of the other team."

In the fourth tier, which is so vast it is split into 18 regional leagues, this was unheard of, but Guardiola’s preparations did not stop there; ahead of Barca B’s season opener he himself went on a scouting trip, casting an eye over a pre-season friendly involving his side’s first opponents, Premia.

He kept a low profile for that trip but he was the centre of attention for the big game itself; between 400 and 500 people would usually turn up for Premia games but 2000 turned out for Guardiola’s managerial debut.

Among them were his father, Valenti, who drove to every game around Catalunya; his wife, Cristina; his two children, Maria and Marius; a number of friends, including Carles Busquets, the father of Sergio and a former Barca goalkeeper; and several of his colleagues and employers, including Laporta and Txiki Begiristain. Alongside him on the bench was his assistant, Tito Vilanova.

The game itself, his very first as a coach, ended in a goalless draw, but his influence was already evident. The scouting trip had paid off.

"From the very first ball I saw that he already knew how we played," Quim Ayats, coach of Premia at the time, told El Periodico journalist Marcos Lopez some years later. "I told our goalkeeper, 'Change, change! Do it even faster'!"

Guardiola’s Barca B squad was made up of young players who had, as Valiente puts it, "Barca DNA", but while they had already been well drilled in the possession football that has come to characterise the club, they were not spared Guardiola’s painstaking attention to detail in his training sessions.

"It happened to all of us at some point," Valiente says. "He would stop training to correct some things, mostly with the defenders and the pivote. He liked to do a lot of work on playing the ball out from the back, and he always tried to find solutions when the opponent pressed us in different ways, and we practised it a lot in training."

Dimas Delgado, one of the most senior players in the team at 25 years old, adds: "He did a lot of work in playing out from the back and being able to receive the ball in the right position, with the right body shape, and how to break the lines. He wanted players to exploit the spaces. He always wanted us to play with one or two touches because it is much faster, everything is much faster."

Barca B won seven of their 10 games after the goalless draw at Premia, scoring 21 goals in total, but Guardiola was not entirely happy.

"In the beginning I had problems," he says, "I remember arriving Monday after a defeat on Sunday and saying, 'Wow, it is not possible to play here', arriving Tuesday and saying, 'Wow, it is so difficult, let’s start to try to find a different way to play.'"

Predictably, those doubts did not last long.

"I arrived Wednesday and said, 'This is what I believe.' The alternatives, the ways we looked at changing what I believe, they did not convince me. That is why I could not change."

Guardiola, after years in the Barcelona first team, had long decided how the game should be played, but for all his ideas, his days as captain at Camp Nou and the fact that his squad were steeped in his philosophy, this was his first experience of actually leading a group of players.

"When you speak in front of guys, whether they are 14 years old, 18 years old in my case at Barcelona, or professional players, it is the same. You are in front of human beings, people.

"It was the first time I sat in front of 20 guys to try to do it. Before one guy told them you have to go over there, and the first time I said, ‘Guys you have to go over there’, so it was completely different."

Johan Cruyff proved particularly useful in that respect.

"He watched some games," Guardiola says of the Dutchman. "In that season I had a lot of meetings with him, I called him at home, we were together. We talked about my doubts, the relationships in the locker room, what happens in certain situations, other things, and of course in that period I spoke many times with him."

The two shared an almost identical view of how football should be played and as much as Cruyff’s advice was welcome on the training pitch, he proved especially useful when it came to the every-day demands of leadership. "He helped me as a manager," Guardiola says. "As a coach the philosophy we connected immediately, but he helped to handle situations with the media, or if a guy has a lot of advertisements, or is distracted with what we had to do. Things like that."

Valiente, the captain, explains how Guardiola put Cruyff’s advice into practice: "Pep had very clear boundaries, he did not let anybody do anything that he thought was out of place. He had a very clear code, you had to adhere to that in terms of the rules, in terms of fines, and I think that was fair. Everybody knew what they had to do, everybody followed a very clear line of what Pep wanted."

Players were fined for being late, for being sent off, for staying out past 11pm and when Guardiola deemed they were not working hard enough in training.

Delgado adds: "It is clear that Pep has his character and when there is something that he does not like or something that he feels we should do better he would tell us in his own way, but he was not - at least with us - a guy who would scream and shout. I remember he was pretty calm, pretty patient, because ultimately he knew it was a process and that we were picking it up and doing well."

They were doing very well. The young squad, featuring the likes of Sergio Busquets and Pedrito Rodriguez, were up against "guys of 29, 30, 31 on artificial pitches in tough conditions", but after a difficult a run of three wins from seven games between October 31 and the start of December, things began to pick up.

"In the beginning it was so difficult, but from midway until the end we were able to play good, to make good build-ups, to make high pressing," Guardiola says.

Delgado remembers their virtues well: "I think the most important games were when we went to the grounds of strong teams around Catalunya, teams who always fought for promotion, and us, being young players, we went to those teams with players who knew the league and the system, where they never made it easy for you, and the truth is that we never changed our way of playing.

"It was our style, it was our philosophy, and it did not matter which team we played, or on which pitch, whether artificial or on grass, it was always the same. We prepared for the games the same way, whether at home or away, and I think that gave us a very, very clear identity."

Victor Sanchez adds: "It was a big change when he arrived at Barca B, and personally I think he improved all of us, he made us understand the game better. It was a huge change."

At the start of the season Guardiola had promised his squad he would buy them lunch if they won three games in a row. It cost him five lunches; Barca B won 16 of the remaining 22 games after their wobbly spell, enough to give them top spot in the Catalunyan section of the fourth tier, and with it a place in the play-offs.

The first game was a goalless draw with Castillo CF on the Canary Islands, but they won the return leg 6-0 to set up a clash with Aragonese outfit Barbastro, who they beat home and away to clinch promotion back to the Segunda B. And the fifth free lunch.

In the end, Barca B finished the campaign unbeaten at home, winning 19 of their 21 games at the Mini Estadi.

But, as far as Guardiola’s future was concerned, results had become irrelevant long before the season ended.

There was a sense that something special was happening right from the very first day.

"I will tell you one thing, Jaume," Premia treasurer Enrique Pimpinela told Jaume Langa, the masseur of Cruyff’s Dream Team, before that opening game. "This kid should be Barcelona manager."

At the end of October, Reus coach Ramon Caldere, a former Barcelona midfielder and Spain international at the 1986 World Cup, told the press that Guardiola would be "one of the best coaches in Spain".

Cruyff himself, according to the well-connected Catalan journalist Luis Martin, recommended Guardiola to Laporta after just 30 minutes of watching his protege’s touchline gesticulations - and not a moment of the game itself - one afternoon at the Mini Estadi.

Begiristain, then the director of football, was also a big advocate of his old friend’s prospects: "We saw his work and his evolution throughout that season with the ‘B’ team and we knew that he would be a candidate for the first team," he tells Goal.

"That’s how it was, and after a difficult season with Frank Rijkaard we decided on a change, and we chose Pep."

Joan Laporta picks up the story: "Everybody around me, I’m talking about Johan Cruyff, about Txiki Begiristain, Rafael Yuste, who was on the board of directors and followed Barca Atletic, all of them told me that Guardiola was ready to be the coach of the first team," the former president told Goal.

"I know it was a surprise because most of the journalists and most supporters were thinking about a coach like Mourinho at that time, but you know... we like to surprise and we like to take decisions for ourselves. We faced up to the pressure and we decided on this young coach."

He explains how the discussions with Guardiola unfolded: "Always we celebrate this date, May 6, that was when his daughter Valentina was born. It was also when I confirmed to him that we had decided to make him coach of Football Club Barcelona.

"But the [first] conversation that we had about this was in February. We had lunch, because I wanted to tell him that in my mind I had decided to put him as the first-team coach if the season with Frank Rijkaard didn’t work. Frank was really happy that I was sincere and I told him in advance, and Frank told me that he wanted to incorporate Pep in the staff of the first team. But in February I talked to Pep just to tell him that I was thinking about putting him as the coach. Pep told me that maybe... I would not be brave enough to take this decision."

Laporta is being polite. This was when Guardiola told him he didn’t have the balls. "Yes!" Laporta laughs. "He said this, and I said that I have!"

Guardiola insists that his response was simple: "Good, we will win everything!". It sounds like one of the typical throwaway comments deployed at his press conferences, but Laporta confirms it is true.

"At that time he told me he would work very hard, and he also said, ‘I know why you want to put me as a coach, because you know that if I am coach we will win everything'!"

Neither man expected that that was exactly what would happen, but they were certainly confident the right decision had been made. Laporta had seen and heard enough by February to convince his directors that the then 37-year-old should be put in charge of one of the biggest clubs in the world, after less than a full season in the fourth division.

It is easy to imagine that Guardiola, at that point without any top-level track record, would have had some reservations. He did not. The confidence in his methods that has helped him transform clubs like Bayern Munich and Manchester City was forged not with Champions League successes at Barcelona, but in those first few months at Barca B.

"When I went to Barcelona and Bayern Munich, and even here in Manchester, when they say to me, 'You cannot play like that here', always I think, 'If I was able to do that in artificial conditions, I can do it here'," Guardiola says.

"I thought that a lot of times in my first season [in England], when it wasn’t going well I thought, 'We can do it, because we did it there'.

"You just insist, insist, insist and do it better. Sometimes when it’s not going well, they say we have to change. No, we have to improve. The fact is there, I had the fact in that year.

"That’s why I could have changed, but I felt it in my skin, and I saw it, that we can do it.

"Working with those players was a dream come true, I remember a lot of times from that period, it was one of the nicest periods in my life."

Illustration by Bartosz Kosowski