Arsenal midfielder Francis Coquelin has refused to use the much-changed team or contentious decisions as excuses for defeat to Olympiacos.
The Gunners missed out on the chance to finish top of their Champions League group after they let an early lead slip in Greece.
Tomas Rosicky sent Arsenal into the break with a one-goal advantage but the visitors conceded twice to make it four games in all competitions without a win.
He told the club's official website: "I'm really disappointed. I think we started really well and we had a great first half.
"When you are winning 1-0 away you want to keep the result and I think the second half we dropped down a level and then obviously they scored the two goals.
"It's a tough place to come but let's not forget we are Arsenal football club and and we want to win. I think we could have won the game and I'm frustrated."
Arsene Wenger's men continue their search for a change in fortunes this weekend when they host West Bromwich Albion.
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