Arsene Wenger endured another tough match in the dugout after watching Arsenal succumb to defeat against Olympiakos last night.

The Frenchman was left frustrated with officials after the Greek side were controversially awarded a corner, from which Giannis Maniatis scored the equaliser. Kostas Mitroglou went on to secure the victory in a match the Gunners had led with Tomas Rosicky’s first-half strike.

The result extends Arsenal’s run of winless games to four, and the under-fire Wenger cursed his team’s misfortune, as he told ITV1, "For their first goal, it was a goal-kick, simple as that."

"What is the fifth referee doing behind the line? Nobody knows. I don't think it was the right decision, but we have to cope with it. After that they scored a good goal."

The Gunners had already booked their place in the tournament’s knockout stages, but the defeat meant they finished the group as runners-up behind Schalke and will be pitted against a group-winner in the next round.

Nevertheless, Wenger was happy with the performance of his team in his 150^th Champions League game in charge. “Some of the younger players did very well for an hour and that is very positive. Also Tomas Rosicky has not played for six months and he had a good 45 minutes and that is the positive of the night.”

Arsenal return to Premier League action on Saturday, when they host West Brom at the Emirates, hoping to bounce back from last weekend’s 2-0 loss to Swansea.