While giving his post-match thoughts, Wenger told BBC Sport: "They pushed us very hard, especially in the first half. They disturbed our build-up and played a very dangerous and direct game. In the second half I felt we controlled the game and did not give anything away.
"[If the West Brom penalty] have been given I would not have said it is a scandal. Looking at the decision again he made the right decision [to play advantage]. It is a difficult decision because if he doesn't give the advantage and he misses the penalty... you are never too honest. I believe he saw an opportunity he could score."
Arsenal have won all three of their home matches in the Premier League this season.