Wenger was pleased by the way Walcott dealt with the attention he received.
"There were some heated moments," Wenger said. "I don't think there was anything exceptional in the tackles.
"Theo Walcott got good treatment today, but I am very happy because the way he responded to it was with full commitment and desire to impose himself.
"That is where you see that Walcott has become a different player recently.
"They know that we try to play a game based on movement and technique and they oppose us with a very strong defence.
"You have to give them credit for the way they defended today, but overall I don't think too much happened. Apart from Theo Walcott, he got a few bad tackles that maybe deserved a yellow.
"Overall it was a physical game with a team who tries to get some points and we expected that. We prepared mentally for that."