The Swede ended a seven-match scoreless run with a brace in Tuesday's 4-0 win.
Arteta said afterwards: "I think he deserved it, because everything that we were seeing in terms of what he was bringing to the team and how much he was helping the team in many areas, apart from scoring goals in the last few weeks, there was no debate about that.
"It was about keeping that belief in himself, that emotional state, that he can enjoy and play freely. I think he's certainly done that today. Again, he was rewarded with two goals, and the biggest smile on his face. Look at his teammates as well in the pictures and videos, they are all so happy for him because he fully deserves it."
Arteta also said: "He makes us a much better team. I think we've become much more unpredictable. He's so physical, he opens the spaces for everybody, the way he presses the ball, holds the ball, he's just phenomenal.
"And then there's icing on the cake, and the biggest thing that we're going to debate about him is goals. He has scored two very different ones today, and hopefully he starts to get some momentum and a good run of goals."