Thomas Vermaelen and Lukas Podolski admitted Arsenal were not at their best in the second half of their 2-1 UEFA Champions League victory over Montpellier.
The French champions, making their debut at this level, took the lead from the penalty spot after just nine minutes through Younes Belhanda after he had been brought down by Vermaelen.
But the Gunners responded immediately with two quick-fire goals from Podolski and Gervinho before being forced onto the back foot for significant spells of the second half.
Manager Arsene Wenger, watching from the stands due to his European touchline ban, will have been happy with the result, but not the performance after the interval.
Vermaelen told Sky Sports: "In the second half we were not great. But in these kind of situations you have to stay calm and not concede a goal.
"The second half was not great, but we had some good performances. We have to stay focused and stay confident."
On the penalty incident, he admitted: "Maybe I have to be clever and not make a challenge. I was 100 per cent sure I could go for the ball, but he gave the penalty."
Podolski scored for a third successive game for the Gunners and has now set his sights on Sunday's Premier League showdown with Manchester City.
The Germany forward said: "Olivier (Giroud) made a good pass for me. I like the situation to be one-on-one against the goalkeeper.
"Like Thomas said, we played very well in the first half, but the second half was not so good. But we have the three points and in the Champions League this is important.
"Now we go forward to the match with Manchester City."