Mesut Ozil then restored the hosts' two-goal lead just before the hour, but Borja Baston's goal and Xhaka's red card left the Gunners sweating right until the final whistle.
Here is how Sports Mole covered the action in North London.
"Bob Bradley has a lot of experience. He's not a beginner, he has travelled a lot and has accumulated experience in the United States.
"He has been in Egypt, France recently and is now in England [i.e. English football], which is certainly a fantastic opportunity for him.
"It's also good for the Premier League - to have an American here will create even more interest for the Premier League in the United States. He is equipped to deal with what is asked of him."
5 - Theo Walcott has scored six goals in five games in all competitions at home for Arsenal this season. Rejuvenated. pic.twitter.com/IIml6hUxxh— OptaJoe (@OptaJoe) 15 October 2016