Speaking toAlgemeen Dagblad, Staam said: "Against Arsenal, Matthijs was traditionally strong and accurate. The tricky thing at United is that it’s hard to see what’s expected of defenders. It’s often a deadlock. The conditions to excel aren’t really created. You can’t really talk about potential anymore. Matthijs is smart and mature and should be a key player by now.
"I sometimes miss the confidence in defence and in the build-up that he had at Ajax. But I’m sure he still has that. Sometimes you’re insecure because of what’s happening in front of you. I know that feeling. Always covering for you and expecting the same in return but not getting it. Then he goes back to the basics, even though he’s a fantastic defender who keeps going. I hope he continues this trend, and we’ll see the old Matthijs again."