Wenger revealed the former Barca youth player did not want to miss out on such a big, and personally emotional, occasion.
"Cesc is desperate to play in every single game," said the Arsenal boss, "and who wouldn't want to play in a game like tomorrow?
"He always wants to play every day and I believe it is the mark of a great player that they want to do that and are happy when they do.
"He wanted to run off the injury on Saturday. I will know tomorrow whether I made a mistake or not in keeping him on the pitch."