Wenger "surprised" Arsenal are first Prem team into last 16

Arsene Wenger is surprised his Arsenal side are the first English team to qualify for the Champions League knockout stages after their nightmare start to the season.

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Two more goals from red-hot Robin van Persie - his 16th and 17th of the season - and Marseille's loss to Olympiacos mean the Gunners have topped Group F.

And with Chelsea, Manchester United and Manchester City all failing to win this week, Arsenal - who came through a qualifier to even get to the group phase - are the first from the UK to progress.

Asked if he was surprised, Wenger said: "Yes - I have to be very cautious what I say.

"I think yes as Manchester United could have qualified [on Tuesday] night, and of course everyone expects Manchester City to qualify.

"It is difficult at that level. I have never played an easy game in the Champions League.

"I have played 150 games in the Champions League and every game gives different problems.

"The groups were very difficult for the Premier League teams. The level has gone up a lot and we were in a difficult group, so I am very happy and pleased to see where we have come from.

"When we drew Udinese in the qualifier you couldn't not bet exactly that we would go through as we did. So overall I'm very happy because we came through a very difficult period.

"We focused, we are united and we worked hard. Together."

Wenger's Arsenal have now qualified from the group stages for the 12th straight season.

Van Persie's first came five minutes after half-time, thanks to a superb assist from midfielder Alex Song.

The Dutchman tapped in his second five minutes before the end when Mikel Arteta's corner was headed into his path by Thomas Vermaelen.

Wenger added: "Van Persie is in a period when he does not have to look for goals. They come naturally for him, always in the right place at the right moment.

"He got two goals from positions that look easy but are not easy. They just come about because he understand game so well."

Song later admitted the Gunners are praying Van Persie's goal spree - which overall is a staggering 38 from 41 games - is not wrecked by an injury.

"It's unbelievable," said the midfielder. "It's very important that he doesn't get injured because if that happens it won't be very good for us.

"Today, and in every single game, he has been unbelievable. We need to keep him in good form."

Wenger added: "At the moment, Robin is an exceptional player. He takes advantage of our offensive style from the wings as we create a lot of chances.

"But I don't deny that he scores all the goals at the moment. We hope that we can keep him fit for a long time."