Rice made a return to his old club and helped the Gunners win 6-0.
Arteta later said: "I'm really happy with him because it was a very emotional and special day for him. He loves West Ham so much, and today he had to focus on the task and what he had to deliver. Set-piece were one of those, because when we have certain players on the field, he can threaten from outside of the box more than inside the box.
"And then I was really pleased to see the class of the crowd as well to give him the reception that, I think, he deserves."
On Rice's danger from set-pieces, he added: "Yeah, it was something that we knew, and we could imagine. It depends who as well who plays in the team, how much height, presence and physicality that we have inside the box to make the right decisions. He certainly has the delivery, he used to it here at West Ham as well, and he's done it in the national team. It's another thing that we can add to his game."