Manager Arsene Wenger accepts Arsenal must learn how to close out games again after witnessing another "fragile" defensive display in the Premier League 3-3 draw against Fulham.
For the second time in a week, the Gunners blew a 2-0 advantage, this time allowing the Cottagers to recover and then lead after early goals from Olivier Giroud and Lukas Podolski had put the hosts in command.
Although Giroud quickly levelled to set up a rousing final 20 minutes, the Gunners - who eventually drew 2-2 in their Champions League tie at Schalke - were unable to fashion a winner, with Mikel Arteta seeing his stoppage-time penalty saved by Fulham goalkeeper Mark Schwarzer.
Wenger knows such costly lapses in concentration at the back must be eradicated if his side are to keep within striking distance of the top four.
"We were defensively fragile, were not cautious enough at 2-0 and we let them back into the game because we lacked urgency," the Arsenal manager said.
"We showed magnificent spirit in the second half, but the team has to learn to deal better with this kind of situation.
"There are good ingredients in this team, a good spirit, but we need a bit more defensively when we are leading the game."
Wenger added: "At the moment, we do not get the points we want. Of course, we now do not have to waste any more time, but I still feel there is good potential in our side."
Arsenal will have little time to attempt to rectify their defensive shortcomings ahead of next weekend's north London derby at home to Tottenham as nearly all of the first-team squad will be away on international duty.
England forward Theo Walcott, however, is a doubt for the friendly in Sweden after coming off with an injury to his buttock muscles.
Wenger said: "We have just to keep working, but it will be difficult now this week because everybody goes away.
"What I can do is pray that everybody comes back in good health."
One positive for Arsenal in the past few weeks has been the development of Giroud.
The France forward, signed from Montpellier in a £13million deal over the summer, now has four goals in as many appearances for the Gunners.
Wenger said: "Giroud had presence and won the long balls. He is dangerous and starts to have belief in what he is doing."
Had Giroud elected to take the stoppage-time spot-kick himself, the 26-year-old could well have ended up with the matchball.
Wenger, though, was happy enough with the Arteta's decision.
"We have penalty takers designated, there is no rule that says if you have scored two, you will score a penalty," said Wenger.
"Giroud had missed a penalty in the League Cup, so you know it can happen to anybody - there are not many players who have never missed when they take them."