The defeat to Manchester United at Old Trafford at the weekend saw the Gunners remain in sixth place in the league, a full nine points off the summit with barely a quarter of the season gone. Wenger has stated that the lead they've already given their rivals may be too much for them to claw back as the season progresses.
"We're very far behind now," Wenger told reporters.
"At the moment you cannot say that [we are good enough to challenge the top three], because we are far away.
"But that's what we have to show, and that's what the target is at the end of the season. We've played away at United, City, Liverpool and Stoke – so we've many difficult away games."But we were poor defensively here. There's no obvious reason for that, apart from the fact we didn't start well and United have quality up front
"They score goals against everybody and they are better than us. It's as simple as that.
"Away to Manchester City we drew 1-1, a good result, and didn't suffer by comparison."Here, I just think we were not on full cylinders and looked much more vulnerable defensively than we did at the start of the season."
The loss to Sir Alex Ferguson's side also saw the returning Jack Wilshere sent off for two bookable offences and Wenger has confessed that he thought about subbing the 20-year-old prior to his dismissal, even though he disagreed with the eventual decision.
He added: "It was very harsh. To me it looked a regular challenge," Wenger told the club's official website.
"Yes, of course [I thought about replacing Wilshere]. But we were in a position where we had to attack and I had no offensive central midfielders on the bench as well.
"I thought I would leave him a bit longer and [the red card] looked harsh from the bench."