Giroud also saw a penalty saved but Wenger believes the France international can now build upon his first goal when he next lines up for Arsenal.
He said: "It was in everyone's mind that the sooner he gets it the better, it was certainly more in his mind even more than in our minds. That is positive of course.
"It was a good finish, he is a good finisher Olivier, but at the moment I believe he is looking for confidence and that goal will help him. I expect him to take that into the Premier League."