This is what Mikel Arteta told the media afterwards:
They're going to assess him between today and tomorrow but when a player has to come off, normally with a central defender - hopefully I am wrong but - normally it's not good news.
No. We had a very clear intention of what we wanted to do in the market with the resources we have and if we can do it, fine. But his fitness [Mustafi's fitness] won't change anything.
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