Ten Hag told a press conference: "I think his off-field issues stop him playing. They have had an impact on him, definitely, so he has to deal with that. So he caused them, so he has to sort them out. We will give him all the support but he has to do better.
"First year he was okay. In the pre-season he was very okay, first four games [of this season] he was very good.But from the moment he was out and then he came back, he didn't deliver the performance we should expect from him and he can do so much better.
"His end product in Ajax was very high and he could return to that level. The Premier League is more difficult but he's capable of doing that."