The Gunners pulled off a comfortable 3-0 win over Dundalk in the Europa League on Thursday.
And Arteta believes it was the perfect result ahead of Saturday's clash with Manchester United.
"We made it look easy because we were very disciplined, took it seriously and were at it from the beginning," Arteta said.
"We made a lot of changes, gave opportunities to other players and I think they performed well.
"We have a large squad and I wanted to give opportunities to everybody. Today they showed they were prepared when I need them and today they made it more difficult me for selection.
"Sometimes it is about the quality, sometimes it is about the tactical plan for the game. I am very pleased with the performance today.
"We missed Willian the last couple of weeks, he had a very short pre-season. He needs that bit of rhythm. He looked good today, great to get some minutes in his legs.
"After losing the way we lost against Leicester it was painful. It took is a few days to react but good to respond straight away with a win and now we go to Old Trafford and try to win again."