In the 111th minute of extra-time of that match against Sampdoria, the Catalans were awarded a free-kick just outside the box, and an assertive Guardiola strode up the Wembley pitch expecting to take it. He had already come a long way, but not quite far enough to command a moment as pivotal as that; for a role owned by someone else. Hristo Stoichkov made that all too clear to Guardiola by pushing him away, and set-piece expert Koeman then so clearly put the ball into the corner of the net by powerfully curling it past Gianluca Piagluca.

Barcelona had finally won their first European Cup, Cruyff’s first and most important big signing had given his team their crowning moment, and Koeman himself had scored what is still regarded as the most important goal in the club’s entire history.

It was not just that they had finally won the most prestigious prize in football, and one so associated with Real Madrid. It was that victory so further vindicated Cruyff’s approach, one that was to then be so deeply ingrained in the club and ultimately take them past their rivals.

Koeman’s classic Adidas-made black right boot from that night is now a centre-piece in the Camp Nou museum but, had things gone a little differently, it could have been Guardiola’s Diadora there instead.

Guardiola still had an important status in the side as a local Catalan lad who had famously been a ball-boy in the doomed 1985-86 run to the European Cup final, though, and went on to offer a moment that became almost as famous as Koeman’s goal. When it came to present the cup, the then 21-year-old did so by stating the words “Ja la teniu aqui” – “here you have it”. Guardiola was deliberately echoing the words of Catalan president Josep Tarradellas. On returning from exile in 1977 after General Franco’s death, he had announced “Ja soc aqui” - ‘Here I am’.

Guardiola felt the identity of the club so deeply, of course, that he would take their new self-determining football philosophy even further. He would hone and develop Cruyff’s ideals, to the point Barcelona moved onto another level when he became manager in 2008.

Seamus Coleman referenced this recently: “[Roberto] liked his full backs getting high and unfortunately at times we conceded too many goals. This manager wants us to be solid first and then build on that with the quality attacking players.”

There is also an argument, however, that difference explains why he hasn’t been anywhere near as successful as Guardiola. To fully implement a philosophy requires that Cruyff-like faith and a lot of investment, but the end result - if a manager is good enough - is that a team more fully understands each other and are more integrated, naturally leading to higher level of play. They can do things faster, and in more devastating a manner.

Koeman has never had the intensity for it that Guardiola does, but that perhaps explains why he has had a more nomadic and less invested career. He is not building legacies at clubs - but he does build good teams.

It may well be good enough to beat City on Saturday. It could come down to those fine details discussed almost three decades ago. Or, Guardiola might again take him aback.