Unassailable, that is, against anyone but Barcelona. "Missió Possible", Catalan television had proclaimed before the second leg, at the Nou Camp a week later. And the world of football weren't disagreeing, with many pundits giving Barca more than a fighting chance of overturning the deficit on home turf.
At least until news filtered through that Messi was not fit enough to take the field.
Bayern subsequently picked up where they left off; rather than cling to their lead in a defensive manner, the Germans set about adding to it in ruthless fashion.
Robben scored early in the second spell to effectively kill off the tie, Gerard Pique followed with an own goal, before Muller made it another rout.
Bayern would go on to beat countrymen Borussia Dortmund in the final, but the more momentous victory had already been achieved, as summarised by German newspaper Die Welt: "The king is dead, long live the king."
What they said:
Henry Winter, Daily Telegraph football correspondent
"This was more than a result, more than a thrilling, ruthless performance by Bayern Munich. This was a statement of German power, of a Bundesliga rampant. Bayern and Borussia Dortmund, the best two teams in Europe, will contest the Champions League final at Wembley on May 25.
"'Football's coming home', sang the Bayern fans at the final whistle, breaking off from their mantras of 'finale' and 'olé'.
"Bayern will next season be led by [former Barcelona architect] Pep Guardiola and it will be fascinating to see how he improves this formidable team. The style he inculcated at Barcelona was magnificent, but all that rich passing was simply bypassed by the speed of Bayern, particularly out wide where Robben and Franck Ribéry excelled."
Daniel Taylor, Guardian chief football writer
"Bayern were simply too refined, too strong and too expertly assembled and, over the two legs, an aggregate victory of 7-0 does not flatter them in the slightest.
"Their place in the final, confirming an all-German event at Wembley on 25 May, was probably assured from the moment the team-sheets were handed in, bearing in mind what has become so apparent over the last few weeks: that Barcelona without Messi can resemble an expensive toy without batteries. Even so, there was something fairly remarkable about the way Bayern comprehensively set about from where they had left off in the first leg.
"The Bundesliga champions had outclassed the most revered club side of the past 10 years and they managed to do so without any of the six players who began the night a booking away from missing the final being ruled out."
Spanish newspaper AS
"Barça have reached the end of a path that was glorious. They have lived the best era of their history. They will win the league, they will continue to win titles and their current model should remain, but if what happened on Wednesday was a casting to decide who is and who is not worth keeping for the future, the club will need to hire every removal company in Barcelona to help with the clearout."
