Speaking to BBC right after the match, the Spaniard explained his decision to change Odegaard as he said: "He had a leg issue, that's why [he was taken off]."
In the post-match press conference, Arteta added: "We can't control [Manchester City]. What we can control is that when we have the run we had when you win, win, win, win, it's easy. The moment is now. After this blow, it's how we react.
"We have the best opportunity to react against Bayern Munich on Wednesday. The team has to show it. If you want to win, you have to overcome these situations. With the games we had, this was going to happen. It is now about how we react. This is in our control."