Robert Lewandowski escaped a red card for an elbow on Laurent Koscielny and then scored a late winner to give Borussia Dortmund a priceless victory over Arsenal in the Champions League.

The Polish striker was anonymous a week ago when on the losing side for his national team at Wembley. He was no standout performer here, but nonetheless had a decisive impact on a match that his side could not lose.

With the match poised at 1-1 and 63 minutes on the clock, Lewandowski challenged for a ball with Koscielny and caught the Arsenal defender flush with a flailing elbow. It looked a clear red card, but referee Jonas Eriksson instead opted to only caution the visiting forward.

It was a puzzling decision and it was brought further into the spotlight when Lewandowski finished a sweet counter-attack, volleying home on 82 minutes from Kevin Grosskreutz's pinpoint cross.

Arsenal, at that point, had been pressing for a winner, but were caught cold by a quite beautiful break from the visitors, who took the goal tally for the season to an astonishing 34 in 14 games.

Arsene Wenger, celebrating his 64th birthday, refused to blame the referee for his side's defeat. Asked about the incident that could have seen Lewandowski exit proceedings, he replied: "I would have to look at it again. The referee was in a better position than I was."

It was a mature response and probably the right one. After all, the Londoners had been created few chances over the 90 minutes and perhaps should have settled for a point that would have edged them towards qualification for the knockout stages.

They had done well to compose themselves after falling behind to Henrikh Mkhitaryan's 16th-minute strike, with Olivier Giroud hitting back shortly before the interval.

This result though has blown Group F wide open, with Arsenal, Dortmund and Napoli all on six points. Arsenal's trip to Dortmund on November 6 takes on renewed importance.

Wenger accepted that his side had not been at their best. "We started a bit hesitantly. Our fluent football going forward wasn't quick enough. We were not at our best tonight."

Until Lewandowski's late intervention, it seemed as if Arsenal had passed a litmus test, proving that they can mix it with one of European football's leading sides.

Dortmund, whose fans sung heartily throughout the tie, started promisingly, swarming around Arsenal's players, and denying them time and space on the ball.

Marco Reus, who scored his side's winner over Hannover in the Bundesliga at the weekend, fired off the first shot of the match and made a telling contribution moments later, robbing Aaron Ramsey of the ball on the edge of the Arsenal area.

Reus then fed Lewandowski, who passed to the lingering Mkhitaryan. The Armenian looked up and drove beyond Wojciech Szczesny. Wenger bristled on the sidelines; Ramsey looked despondent.

Under the same circumstances last season Arsenal might have crumbled, but they held their nerve and fought back. Tomas Rosicky had an effort cleared off the line by Mats Hummels and a deserved equaliser eventually came on 41 minutes.

Ramsey spread the ball out wide to Bacary Sagna. The Frenchman placed his cross in the awkward area in between the keeper and last defender. Neven Subotic and keeper Weidenfeller failed to deal with the ball and it was Subotic's touch that teed the ball up nicely for the lurking Giroud to smash home into an empty net.

The Emirates erupted yet half-time came at the wrong time for Arsenal. They had been in the ascendancy, but Dortmund regained control of the match after the interval. The industrious Jack Wilshere was tiring, perhaps still feeling the effects of a kick on the ankle he received in the first half, and it was no surprise when he was withdrawn on 58 minutes for Santi Cazorla.

The little Spaniard injected life into his flagging team, his ability to dictate the play with first-touch passes helping Arsenal to retain possession.

There had been little in the way of goalmouth action and it was to Dortmund's credit that they had restricted Arsenal to so few chances. Moments after Lewandowski's lucky escape, Cazorla was denied a winner by the crossbar. It proved to be a rare opening for the home side.

Arsenal continued to probe, but their enthusiasm proved their undoing. Dortmund are renowned masters of the counter-attack and, when Arsenal lost possession, the visitors broke at speed. There was a air of inevitably about the winner as Lewandowski rattled in a volley, despite Szczesny efforts to make himself as big as possible.

Wenger's side will need to up their game to escape a tough group, especially with away trips to Dortmund and Napoli to come. The Frenchman remains confident, however. Asked about the state of Group F, he said: "(It's) tight and difficult for us, but possible ... we need a result away from home, but we can do that."

With matches to come against Chelsea, Liverpool and Manchester United in the next three weeks, as well as a weekend trip to Crystal Palace, Arsenal do not have time to be despondent.