Ahead of their Europa League clash with Benfica, Arteta was asked about his young winger.
He said: "His form in recent months shows that he's a very important player for us. I think he's getting better and better, his performance levels have been really consistent, so that makes him for sure one of the most important players in recent months.
"It is very unusual but he's been doing a lot of unusual things. He's dealing with things at his age in a very unusual way, but that's why he's showing what he's showing, because his maturity is above his age and so is his intelligence as well."