Arsene Wenger recently criticised his side’s rearguard following Martin Demichelis’s equaliser for Manchester City in the 2-2 draw at Emirates Stadium last month.
And Arsenal vice-captain Mertesacker accepts that there is room for improvement in that area.
“We have to go through the set-pieces and say what went wrong because last year we had quite a good record,” Mertesacker told Arsenal Player.
“We need to improve on it this season because we’ve conceded from them already.
“It’s all about reminding ourselves how good we are in the air from set-pieces, but we have to get to the ball and stop opponents getting into dangerous areas. That’s what we need to improve. We had a good record throughout last season but we need to find that again quickly.
“[Attacking corners] is a part we have to improve as well. The deliveries, the timing, there’s a lot of detailed things we have to improve. A lot of it has to do with concentration, strictness and good deliveries and good timing.
“When we went through the situation we could see that not everyone was on the ball. We have to be able to score or avoid conceding goals. We have to make sure that we are ready and concentrating on every set play.”
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