Ethan Nwaneri scored a first senior goal for the Gunners, with Gabriel Jesus and Kai Havertz also on the scoresheet.
Arteta later said, "Very good. We talked about that - play with enthusiasm in these games, play with the right attitude and commitment, we certainly showed that so very happy to be in the quarter finals."
Discussing teenager Nwaneri, he continued: "He did it yesterday in training so we’re getting used to that. He’s a big talent, he’s got the right attitude, he’s got the right players and context around him and we need to make sure that we put brick by brick. But we have some player there!
"He wants to make every ball, he wants to make things happen. Outside, around the boys, he’s still a bit quiet but that’s usual. He’s still only 17-years-old. His work ethic is tremendous and he loves what he does.
"He’s there. He’s showing every day what he’s capable of. You see his teammates, they give the ball all the time. That’s a great sign. We’ve got some player there."