Walcott has not started a league game since August amid claims that problems with his ongoing contract talks are the main reason for him not starting.
But Wenger is adamant that Walcott's current absence from the starting line-up is due to illness and nothing more.
"I will make a decision on when I know how fit he feels, this is a digestive problem," said Wenger.
"He has been sick and did not train, so we will see how he is.
"It is nothing linked to his contract at all, it's because I have played other players, simple as that. We started the season well, he was injured too.
"He played 40 minutes on Saturday, you can't say he's not played."