Arsenal manager Arsene Wenger admitted his side were nowhere near their best, saying Manchester United deserved to take all three points against the Gunners, while adding his side were nowhere near the form needed to compete for the English Premier League title.

Robin Van Persie and Patrice Evra scored in a 2-1 win for the home side at Old Trafford, with Santi Cazorla netting the consolation goal for Arsenal. While the scoreline might suggest a close game, it was hardly that as United completely dominated the away side from start to finish.

"I'm disappointed of course, because we had a lot of the ball but we were not very efficient in our final third or in their final third," Wenger said. You feel it was a bit (of) an illusionary domination. We had a lot of the ball but they created more chances and deserved to win the game.

"Part of that is down to the fact that we gave an early goal away. In a game like that, that's a massive advantage. Then they defended well, were sharper than us in the duels and the consequence is you lose the game."

Wenger insisted the fact that the first goal was scored by Van Persie did not have much of an effect, with the final score the only thing that matters. "Honestly, that doesn't bother me at all," he added. "That doesn't matter.

"What you want is to win the game. You don't care about who scores in their team. What is most important is that you don't make a mistake at the back and you don't give chances away."

Jack Wilshere was sent off for Arsenal in the second half for a second bookable offense, with the young midfielder treading on Evra's foot after initially losing control of the ball, but Wenger felt the red card was harsh.

"It was very harsh," Wenger said. "To me it looked a regular challenge. 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.

"I was surprised that (the referee) gave him a second yellow card. He went for the ball and Patrice Evra made the maximum of it. What is unbelievable is how naive the referee can be. When he says in front of the other players, 'the next foul and you are out', of course the next foul the players dive like they have been killed and that's what happened."

Wenger also admitted Arsenal were not playing like a team capable of competing for the English Premier League title. "We were poor today defensively I think," Wenger said. "There's no obvious reason apart from the fact that we didn't start well and that Man United have quality up front.

"They score goals against everybody and (were) better than us. It's as simple as that. "I think today we were not good. At Man City, we played a 1-1. We had a good result and didn't suffer from comparison. Today, I just think at the moment we are not on full cylinders and we looked much more vulnerable defensively than we were at the start of the season.

"That's what we have to show (that the team can compete for the title). At the moment, you cannot say that because we are far away. But that's what the target is until the end of the season.

"We've played many away games now in many difficult places. We've played at City, at United, at Liverpool, at Stoke. So we have many difficult away games. But we are very far behind now."