The striker has been dogged by injury problems over the last two years, and although this latest setback is not thought to be a serious one, he is likely to miss the League cup clash with Doncaster on Wednesday night.
As for the game itself at Stamford Bridge, it was a much improved display by the Gunners, who ended a five-match losing streak at the home of their rivals.
Arsenal might have won at Chelsea for the first time since October 2011 but Alexandre Lacazette shot wide after Aaron Ramsey had hit the post.
It was a far better performance than the 4-0 loss at Liverpool, though, much to the delight of Wenger.
Wenger said: "You have only one way to respond, on the pitch. That's what we did. It was vital for us, even above the result, to come out with a solid performance.
"We could have won it. It was an intense game between two teams going for it...defensively we were much more stable. I believe we were focused, determined and showed character. If we weren't we couldn't get away with a point.
"We have the capacity to be strong away from home and we've shown that today. I think to play in a positive environment is very important but that starts with your own performances."