Eight years ago, they were three boys with dreams. But even the imaginations of those supremely gifted 15-year-olds would have struggled to foresee a moment as emotive or arresting as the scenario due to play out on Wednesday evening in London.
The team photograph, taken in 2002, tells so much of the story. Lionel Messi, the slightest among the group, is caught speaking to a team-mate when his attention ought to be on the camera. Cesc Fabregas, also distracted, his face unmistakable. Gerard Pique, towering over many of his peers, shaping into the defender who won the Champions League last year. At FC Barcelona, in the youth teams as much as with the seniors, standards are high – but it comes as little surprise that this group of players, with a spine of future world-beaters, are still referred to with reverence as the "Baby Dream Team".
When they meet next week in the quarter-finals of the Champions League, the three will be on the pitch together representing their clubs for the first time since their Barça Under-16s days. Extraordinary for them, and for Albert Benaiges, the man who has overseen youth development at Barcelona for more than a decade. The 2002-03 season is one he will never forget, as the Under-16s won an unprecedented treble. Messi scored 30 goals in 37 games playing as a second striker. Behind him Fabregas was the elegant holding midfielder who never put a foot wrong. And behind him was Pique, a baby-faced colossus marshalling the defence.
"Messi came alive when he was on the pitch," Benaiges recalls. "Everybody said that he was really special but very small. But he had qualities that you very rarely see – this incredible change of pace and the ability to run with the ball so close to his feet."
His transformation once the match began bamboozled even the officials. Juan Pallarés was a young referee during that season, running the line in the Catalan derby between Barcelona and Espanyol. He remembers: "They told me that there was a player in the match who was well on his way to becoming a great but when I saw him he looked very shy and quiet. On the pitch, Leo was completely different, demanding the ball, going past players at every opportunity and never holding back despite all the fouls. Occasionally he dropped over to my wing and did something special. I lost track of whether or not he was offside. It was only later that I realised that Cesc and Pique had also been in that team."
The other two, however, were not unnoticed by Benaiges. Pique was a jewel in the Barcelona crown, and Benaiges remembers being left in no doubt how far he would go. "He was spectacular," Benaiges says. "With Pique you knew that he was going to go on and play for the first team. You knew he had the potential to be the best defender in the world.
"I remember Pique being left here by his dad when he was seven or eight years old. He seemed like a flamingo with the long gangly legs. He was a little bit uncoordinated but we worked on that and on his heading and the results are there for everyone to see."
Pique's attitude, like that of Fabregas and Messi, brings as much pride to Benaiges as memories of the ability they showed at such a young age. The rather rotund guardian of Barcelona's youth academy is a throw-back to Liverpool's fabled boot-room of the 1970s. Barcelona's youth team is built on old-fashioned values. And he speaks about Fabregas in particular as being not just a Barcelona player but a 'Barça kid'.
Benaiges believes the fact their youth system puts as much emphasis on forming young men as it does on forming young footballers stood Fabregas in good stead. "Cesc is a Barça kid – very well balanced and well behaved," he says. "What always set him apart was his character. His leadership, his nerve and his determination."
Is there a particularly painful sense of loss, knowing that Fabregas moved to Arsenal at the end of that season, in the summer of 2003? If there is, it does not show. "The move worked out well for him. Now he is a fundamental player with Arsenal and with the national team." Benaiges disputes the fact that Barcelona lost one of their three big stars because they did not value him. "I don't think he was undervalued as a player, certainly not in terms of how the coaches viewed him. I don't like it when it happens but the truth is it worked out well for him. Sometimes they go and they get paid great money and it goes to their heads and everything goes wrong. But not with Cesc."
His praise of Messi also centres on the attitude of the then 15-year-old. "He did something that says so much about him because a lot of young kids don't like doing it. In one year he played with the Barça C youth team, then Barça B and then with Barça A. But then he went back and played for Barça C again afterwards.
"You could say to him, 'Look here's the ball, let's play a match' and he would get on with it. He just loved playing. He didn't mind what level. Some kids when they play for the A team and then you ask them to play for the B team they pull a face but with him he always gave everything." Messi had a harder time than Fabregas and Pique. The latter two were local lads. Fabregas, born just north of Barcelona in coastal town Vilassar de Mar was picked up aged 13 playing for Mataro. Pique's grandfather Amador Bernabeu is a former vice-president of Barcelona.
But Messi signed as a 13-year-old from Argentina after doing enough in the first five minutes of his trial against boys three years older to convince Barcelona he was going to be something special in spite of his size. He was 4ft 6in when he turned up but eventually sprouted to 5ft 5in injecting himself with growth hormone treatment, paid for by the club every day until he was 15. "Just as the bright kids want to go to Harvard, Messi wanted to trial with Barça," his dad Jorge once told me. Jorge, along with wife Celia and his three children, also came to live in Barcelona. Messi's mum and siblings all had to return to Argentina shortly after he arrived. He was left with his dad in a strange city, and unable to even play, first because of injury and then because of paperwork problems.
Fellow trainee and current Barça reserve Victor Vazquez (he is one of only three other players in the Baby Dream Team to go on to professional football: Marc Valiente, now at Seville, and Marc Pedraza at Espanyol are the others) remembers those early weeks. "The first few days he sat in the corner and never said anything. He was very shy until one day Pique, Cesc, and myself went over to talk to him."
Jaume Marcet, who covered the young team's progress for the club's in-house television channel, also remembers Messi's frustrating start. "I would see him at the games not even sat on the bench but in street clothes because he was not allowed to play," he recalls. "He had come all this way to play and he was not able to."
"We put to him the possibility of us all going home but Leo was adamant that we should stay," remembers his father Jorge. And finally the injuries cleared up and clearance from Newell's Old Boys came through. Aided and abetted by Fabregas and Pique Barcelona's Under 16s won the Spanish and Catalan Championships and the League.
"What he does now on the pitch he did when he was a kid," remembers another youth team coach, Alex Garcia. In the final of the Catalan Championship he played with a mask to protect a broken cheek but it annoyed him so much he took it off, creating panic on the Barça bench and provoking his substitution – but only after he had scored twice to secure victory.
Marcet also remembers Fabregas's role in that fabulous season before he was whisked away by Arsène Wenger. "He was sometimes more inconspicuous than the other two," he says. "I did not really notice him at first but talking to ex-players at the club they would say, 'Watch Francesc Fabregas'. And when you focused on him you saw that he did not make a single mistake ever. "
That glorious season should have been the springboard for Pique, Cesc and Messi to reach the first team together but in 2003 Joan Gaspart was replaced as club president and before new man Joan Laporta had installed sporting director Txiki Begiristain, Fabregas had moved to Arsenal.
Marcet says: "When Cesc left there was a feeling that maybe he was doing the right thing. It would be hard to break into the side with Iniesta and Xavi playing in his position. I'm sure he kept in touch with Pique and maybe that influenced Pique's decision to go to England."
So perhaps Wenger is the real winner in this tale. On Wednesday he will have one third of the spine of that all-conquering youth team. "When Cesc arrived here I spoke with his mother and she told me that his team used to winning 6-0, 7-0, 8-0 and 9-0," Wenger recalls. "At that time Cesc, Messi and Pique were in the same side so I was not at all surprised."
With their shared history, it is unsurprising that rumours of Barça's interest in luring Fabregas back, just as they did with Pique, will not go away. Could the three be sharing the same dressing room again next season? The stars of the Baby Dream Team would now have a combined price in excess of £150m. And Wenger would clearly not want to let Fabregas return.
But still, Benaiges can dream. "Cesc is Barça through and through," he says. "I would love to see the class of 87 [they were all born in that year] back together but it is not me who decides. If the president wants him and, more importantly, if the coach wants him then of course he would be welcome."
*Born: 4 May 1987, Vilassar de Mar
*Age on Arsenal debut: 16 years, 177 days (after joining in Sept 2003)
*Appearances: 265; Goals: 46
*Major honours: Won the FA Cup in his first full season at Arsenal (2005), and played a part in Spain's Euro 2008 triumph.
*Born: 24 June 1987, Rosario, Argentina
*Age on club debut: 17 years, 114 days
*Appearances: 134; Goals: 79
*Major honours: World Player of the Year, European Footballer of the Year, 2009 treble (Champions League and domestic double).
*Born: 2 February 1987, Barcelona
*Age on Barcelona debut: 21 years, 224 days. Previous clubs: Manchester United and Real Zaragoza.
*Appearances: 131; Goals: 11
*Major honours: Champions League (at United) and Euro 2008 winner, Barcelona's 2009 treble.