The Blues are yet to record a clean sheet this season and the wait will now go into the eighth game of the campaign away to Fulham next Saturday.
“I think we need to improve our defending at set-pieces because this has been a problem for us this season,” said Mancini.
“We can do better and we need to work on this area. We are finding it hard not to concede at the moment and we are probably two points worse off than we should be so far this season.
“I’m frustrated and the players are frustrated but we will get things right, I’m sure. We didn’t play very well today and we were getting a little overrun in the first half which is why I changed Sinclair for Rodwell.”
Responding to whether he believed his players were still thinking of the events of last season, Mancini said: “I hope not. What we did is in the past, now.
“We should have held on to our lead but this has been a problem for us lately. We played too deep and invited trouble.”
Arsenal boss Arsene Wenger was pleased with his side’s performance and felt his team should perhaps left with more than a point.
“We deserved a goal for the spirit and quality we showed in this game,” he said.
“I was disappointed Gervinho didn’t find the target when the score was 1-1 but this result will hopefully reinforce the belief and confidence we have to well in the Premier League this season.”
