The Gunners had a penalty appeal dismissed in a game where both Emmanuel Eboue and Cesc Fabregas sustained injuries.
Wenger told Sky Sports: “It was a disappointing result as we played against a team who played in their own half.
“I felt we had back luck as well. We were punished when Eboue was kicked off the park and we had a penalty turned down.
“I would like to see what the fifth the official is doing. It has been proved again tonight that it is absolutely useless this system.
“It was a difficult performance. We needed to be patient. We didn’t create many chances.
“It was a difficult game against a team who used all the tricks to slow the game down.
“For us we needed not to make a mistake but unfortunately when we were down to 10 v 11 we were open at the back.
“We made a mistake and they took advantage of it. We did not communicate and that’s where we were punished.”
“But I am confident we will qualify.”
