Arsène Wenger says his team have showed strength to "shorten the crisis" since their back-to-back cup defeats.
Blackburn Rovers and Bayern Munich won at Emirates Stadium earlier this month to knock Arsenal out of the FA Cup and leave them long odds to progress in the Champions League.
But a hard-fought 2-1 win over Aston Villa arrested the decline and has given Wenger renewed hope ahead of Sunday's north London derby.
"We were very down after the Bayern game but we responded well," said the manager.
"I believe that strength of a team is to shorten a crisis. Where one team loses two games, some lose six. So it was a vital game against Aston Villa, who recently had a good record away from home.
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"We managed to win the game, people said we won [unconvincingly], but we won. So the atmosphere was a relief, there was no euphoria but there was relief and we want to build from that.
"Every defeat makes you weaken quickly," added Wenger. "We have recently just seen Barcelona lose two games. Look at the damage it had on their confidence in the second half against Real Madrid [in the Copa del Rey].
"It is quite amazing how fragile a team can become with such big strength because of just two knocks. Every team needs confidence to express its potential."Copyright 2015 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source