Mikel Arteta has insisted that Arsenal cannot afford to let their Champions League collapse against Anderlecht on Tuesday happen again.
The Gunners surrendered a three-goal lead at the Emirates Stadium as the Belgian side, who only have two Group D points, came back to draw 3-3 in the second half.
Arteta, who scored Arsenal's first last night from the penalty spot, has admitted that the Londoners missed a "tremendous opportunity" to secure their qualification to the knockout stages and will analyse what happened to ensure that they do not let such a position slip again.
"When you are 3-0 up, in a big game like this, an important game like this, because we could have been through the group stage, we missed a tremendous opportunity," Arteta told the club's official website. "You can't afford to make mistakes like this and give any hope to any team in the Champions League because they have the quality to hurt you and that's what happened.
"We can't give those chances away because you don't know what's going to happen in the next [game]. When you have opportunities like this, being 3-0 up, it doesn't get any better than that, so we are very frustrated, very disappointed. We need to analyse what we've done because it's not good enough.
"We are too upset [to say anything else], but we have to analyse what happened and it can't happen again."
Two points from their remaining two games will guarantee Arsenal progress to the tournament's last 16.
