Bayern manager faces his biggest challenge to date in nullifying his boyhood club, writes Jason Burt
There will be an image of Pep Guardiola that will be replayed time and again ahead of this week's Champions League semi-final first leg between Barcelona and Bayern Munich.
It came from only last March when Guardiola, whose first return to the Nou Camp had been heavily trailed, arrived in time to watch Lionel Messi nutmeg Manchester City's James Milner as part of an extraordinary performance from the Barcelona icon that evening.
Guardiola, who remains a season-ticket holder in the lower main stand, sat with his parents and his friend, Manuel Estiarte, and at that moment his face betrayed the joy of every fan and football lover as he rubbed his hands across his features in disbelief. But Guardiola also betrayed the fear of any coach who could potentially face Messi also as maybe he felt that evening it was destined to be. There was a look of, 'How do you stop that?' How, indeed, do you stop that? But then, Gerard Pique, the Barcelona defender who, like Guardiola, is so steeped in the club's history and DNA, says that there is more to the team now than a fixation on Messi. That, he suggests, is what makes them even better. Even more explosive. Even more potent.
Since Guardiola left in 2012, physically and mentally exhausted and desperately in need of the year-long sabbatical that he then took by moving to New York, Barcelona have added Neymar, they have bought Luis Suarez. It is not such their ability, but their chemistry that is so remarkable according to their team-mate.
"We're talking about three of the best players in the world here.I've never seen a relationship like the one between Luis, Ney and Leo," Pique said. "They get on superbly - no hint of jealousy - and that shows on the pitch."
The attacking trio, all from South America, have scored 102 goals between them this season already beating the 98 goals that Messi, David Villa and Pedro struck for Guardiola's Barcelona in 2010-11 and the 99 by Messi, Samuel Eto'o and Thierry Henry in 2008-09, the coach's first season in charge.
Despite Pique's claims there is no suggestion that this side has yet suggested it can match the team that Guardiola coached, which won 14 trophies in four years, but it has a goal-threat that means they can sweep away any team on their day: including Bayern.
There has been much debate as to extent to which Luis Enrique, the current Barcelona coach, has changed the team's style also but Pique, in an interview with Champions magazine, the Uefa publication, ahead of the semi-final, maintains it is fundamentally unaltered. But with key differences.
"I think the style is the same as it has ever been," the Spanish international said, before adding: "The style which has been here since [Johan] Cruyff came to Camp Nou: it remains the same. We have to have the ball, to dictate possession, to control games through possession and create a lot of chances. I've never seen a Barca team that doesn't control a game, doesn't have a lot of ball possession and lets the opponent attack all the time, because we've maintained that style."
Above all, Guardiola will have to think differently in having to combat an opponent whose attacking threat is even greater than his - especially as he will be miss the injured Arjen Robben whose pace would have hurt Barca on the counter-attack.
Among the changes made by Enrique is an altered role for Messi, moving him wider, into positions he used to occupy before Guardiola turned him, partly at the Argentine's behest, into a more central striker, or a "false nine".
"Leo is someone who can read the matches perfectly and he is very smart," Pique said in his Champions magazine interview.
It does seem a far cry, a different world from not so long ago when Barca were struggling, Messi appeared unhappy and distracted with even chatter that he might want to leave and it seemed conceivable that Enrique, like Guardola a former player at the club, would not survive the campaign.
"Every coach is different," Pique said. "Luis is a coach who likes us to press a lot high up the pitch and when the opposition attack to mount fast counter-attacks."
There are 21 European Cups between the four semi-finalists - with the other last four meeting between Real Madrid and Juventus containing clubs who have actually claimed it more times: 12. Albeit 10 of those victories belong to the holders, Real. That tie also has the backdrop of a coach returning to his former club with Carlo Ancelotti going back to Turin - even if the Italian's time there, during the early years of his management career, was far from successful.
In fact in his second season in charge Ancelotti's sacking was revealed at half-time during Juventus' final league game of the season. Juve still had the chance to win the title. They lost. Guardiola's departure from Barca was far less brutal, the reception on his return will be largely warm, although he will be fearful that he could be left, if Messi, Suarez and Neymar are at their mesmeric best, with his hand across his face again. But without the smile that accompanied it the last time.