Emirates Stadium boss believes nervous fans angered by lengthy lean spell are affecting his side’s performances.
Arsenal’s hopes of securing a top four finish are being sorely tested following a couple of poor displays against Southampton and Man City.
Arsene Wenger’s team are six points behind fourth placed Tottenham in the race to qualify for the Champions League and have a tricky trip to Chelsea next weekend after a midweek FA Cup replay against Swansea.
With Mikel Arteta facing three weeks on the sidelines with a calf strain and Koscielny now suspended, Wenger’s players are in for a stern examination of their character.
Yet Wenger refused to criticise Dean for sending off Koscielny and instead admitted he was frustrated with the way his players started such an important match.
“It (the red card) is not really important, you have to deal with the decision. I heard it was a penalty. Was it a red card? I don’t know,” he said.
“We started too timid and didn’t have enough confidence or authority. When you play at home in a game like that you have to dicatate it and we didn’t, especially defensively.
“It is frustrating because after that the team showed great heart and gave everything.”
Wenger believes the negativity shown by many Arsenal fans after eight years without a trophy makes his already-nervous players even more anxious.
“We are a bit too nervous to play in a serene way at home. I don’t know if it is linked with that (the crowd) but it doesn’t help,” Wenger said.
Although Arsenal are clearly struggling at present, they finished third from an equally unpromising position last season.
“We are in there of course and we have to fight until the end of the season,” Wenger added.
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