The Welshman continued his magnificent scoring form to secure three points for the Gunners in a tight clash at the Westfalenstadion
The Welshman claimed the victory, which leaves the Gunners top of Group F in the Champions League three points clear of third-placed Dortmund, had left the Gunners feeling "over the moon".
"It was a great achievement from the lads," he told Sky Sports News.
"It’s a difficult place to come and the fans were magnificent tonight – they stuck behind us and we got the win."
"We were good defensively. It was a great away performance. We defended ever so well and got them on the counter attack. We’re over the moon."
"I’m enjoying myself at the moment. I’m delighted with the way I’m playing but it was a great team performance and result."