Arsene Wenger admits he faces a task lifting his Arsenal players after they were held to a 1-1 draw by 10-man Atletico Madrid in the first leg of their Europa League semi-final on Thursday night.
The Spanish side played over 80 minutes with a numerical disadvantage after Sime Vrsaljko was shown a second yellow card at the Emirates Stadium, but the Gunners were unable to make the extra man count.
Alexandre Lacazette broke the deadlock with a fine header from Jack Wilshere's cross after 61 minutes, and it appeared Arsenal would head to the Wanda Metropolitano next week with a slender lead.
But Atletico punished Arsenal's failure to take their chances as Antoine Griezmann pounced on defensive uncertainty to score a vital away goal eight minutes from time, with Laurent Koscielny unable to deal with a routine long ball.
But Wenger said: "It's not about blaming individuals. The whole team is very disappointed and down.
"For us to have a chance to qualify, first we must rebuild and get the disappointment out of the way. To rebuild the confidence and desire to go there and qualify. Our fans were fantastic, and that's what we want."
Arsenal could have been out of sight by half-time as Lacazette, Danny Welbeck, Koscielny and Nacho Monreal all saw chances come and go with Atletico camped inside their own half.
Atletico always posed a threat with Griezmann having two snap-shots of his own, but Lacazette and Aaron Ramsey had chances to extend Arsenal's lead before the ultimate sucker-punch.
"We created the anti-climax by giving a goal away," Wenger added. "I was focused on doing absolutely everything to win the game.
"We played the favourites out of the four teams left, and I thought we started well with good pace and good collective drive. The whole thing went wrong in the end, but I don't have much time to get rest."