Despite his impressive showing, a decision regarding Hein's future at the club looms large. The 22-year-old Estonia international signed a long-term contract extension in the summer, but the arrival of England youth international Tommy Setford from Ajax suggests Hein might be loaned out to gain regular playing time.
"That's the conversation we are having," said Arteta.
"Obviously, David and Aaron are away at the moment and we are really really short in that position, but we want to develop our players - especially a player like Karl who has big potential and a big future ahead of him. He needs to play games, so we're going to explore that option as well."