Luis Enrique admits his Barcelona side need a "heroic performance" to stand any chance of overturning a humiliating 4-0 defeat to Paris-Saint Germain in their Champions League last-16 first-leg tie on Tuesday.
Angel Di Maria scored twice for the home side, while Julian Draxler and Edinson Cavani were also on target in a sensational PSG performance.
The scoreline matched Barcelona's worst ever Champions League defeat and left Luis Enrique at a loss to explain his side's display.
"It is difficult," he told reporters after the game at the Parc des Princes. "They were superior to us from the start. It was a disastrous night for us in which we were clearly inferior.
"There's not much more to say. PSG did what we expected them to do and produced their best version and we were at our poorest."
Barcelona have not been eliminated prior to the quarter-final stage of the Champions League since 2007 but the task facing them is enormous.
No team has ever gone through after losing 4-0 in the first leg of a European tie.
"It's extremely difficult for us now but we go back to our stadium and really we need a heroic performance," the Barcelona boss added. "But why not dream?"