Mikel Arteta is determined to lift Arsenal's shell-shocked troops after their last-gasp exit from the Europa League at the hands of Olympiacos.
A goal from Pierre-Emerick Aubameyang appeared to have rescured the Gunners in extra time, but the Greeks bagged a goal at the death to win it on away goals.
The new Arsenal boss admits he has to get his players believing again to ensure the progress under him is not undermined by the surprise loss, starting with Monday night's FA Cup tie at League One Portsmouth and West Ham at home next weekend.
"We have to move forward together and I have to lift them," Arteta said. "It's my job. We need to learn from it and improve as a team.
"Looking at the table, we are still far from the objective that we still have but we have to keep fighting for it, game by game.
"It hurts big time. We had a lot of hope in this competition. I know how much they wanted to win it and it's a difficult one to digest as a team and a club.
"I think we did a lot of positive things in the game. I think we created enough chances to win the game, but if you concede two set piece goals in a tie like this, you put yourselves in big trouble.
"If we had gone through, energy wise, it would have given us a big lift and brought everyone together. It's a big disappointment. But I'm right behind the boys and the effort they put in the game. It was enormous."
The Arsenal boss added: "I think we've got enough goal threat in this team but we have to put the chances to bed. In the opposition box, you have to be ruthless and we weren't tonight.
"I just want to concentrate now on lifting those players, getting back their belief and convince them that there's still a lot to play for and move on. We have to react as a team."