The "saddest night" was how one Catalan newspaper's front page described Barcelona's biggest European defeat since the 1994 Uefa Champions League final.
Barcelona did not have the opportunity then to avenge their loss to AC Milan. But this time they still have the slimmest of chances against Bayern Munich despite going into next week's second leg trailing the Germans 4-0.
Barcelona beat Bayern 4-0 at home on the way to the 2009 final, but today's Bayern are much tougher opponents.
In their last eight matches, all victories, they have scored 36 and conceded four.
Twenty points clear at the top of the Bundesliga, they were crowned champions almost three weeks ago.
In contrast, the intensity of Barcelona's performances has diminished in recent months.
Defeated in the first leg of their last 16 tie by Milan and then held by Paris St Germain in the quarter-finals in Paris, their progress was dependent on home performances.
Barca were impressive and intense against Milan, nervy and fortunate against Paris. They started as underdogs in Munich with good reason.
Barca's problems have been many.
Losing their coach, Tita Vilanova, to cancer treatment for three months was damaging. Also, they did not buy a top-class central defender at the start of the season. Injuries subsequently decimated their back four.
A hamstring injury to Lionel Messi did not help and it is doubtful that he has fully recovered. The world's best player was anonymous in Bavaria, though he received almost no service from a team unrecognisable from their usual dominant selves.
The prospect of a first Barcelona-Real Madrid European Cup final looks remote now, but Barcelona will hope for some advantages in the second leg.
Messi should be fitter, Carlos Puyol should be back alongside Gerard Pique.
The centre of the Camp Nou pitch will not be purposely flooded to disrupt their play as it was in Munich and they would be very unfortunate to have a repeat of the poor officiating which cost them in Germany, especially when they conceded their second and third goals.
The tie is rationally beyond them, but if there is any team who can do it then it is Barca at their best.
The problem is getting to their best, especially when Vilanova seems so reluctant to make changes during the match.