Arsene Wenger says Arsenal produced a “complete team performance” against Olympiakos to seal qualification for the last 16 of the Champions League.
French striker Olivier Giroud scored a hat-trick as the Gunners won 3-0 in Athens on Wednesday.
It means Arsenal reached the knockout stages for the 16th successive season.
When asked if it was one of his best European wins, Wenger said: “Yes, because we needed a perfect performance. I’m very proud.”
Arsenal needed to win by two clear goals in Greece following a stuttering campaign which saw them lose their opening two games against Dinamo Zagreb and Olympiakos.
They were also hammered 5-1 by group winners Bayern Munich, but recovered to qualify with an accomplished display in Greece.
“I told you before the game it would be the greatest escape,” Wenger told BT Sport.
“It is a fantastic achievement for us. When you look at who we’ve lost in the last three weeks, we’ve lost Francis Coquelin, Santi Cazorla and Alexis Sanchez among other long-term injuries. Not many people gave us a chance.
“We are a real team. In the dressing room this team is very close and you could see that again today.”