Arsenal's progress under Mikel Arteta has come largely in baby steps. There have been some bigger strides too, though, and this was undoubtedly one.
Last season’s FA Cup success came courtesy of a win over Manchester City in the semi-final and then Chelsea to lift the trophy. They were significant victories.
In the Premier League, however, it is a long time since Arsenal found a result away from home to resemble this. They hadn’t, for example, won at Old Trafford for 14 years.
The problem inherited by Arteta almost a year ago was that Arsenal had become predictable on occasions like this.