The Manchester United marksman - his country's leading scorer in qualifying - missed six weeks towards the end of the Premier League season with a knee injury.
Van Gaal said: "He is coming out of injury, you know that. We built him already up in our federation, our medical department.
"It was under the permission of David Moyes. So we could control him. He has worked very hard. Then he played two matches of 20 or 30 minutes and the last match 30 minutes.
"We did not expect that as the injury was bad. It was not so light. De Guzman [who suffered a hamstring injury in training on Monday] was much lighter I think.
"Van Persie had a heavy injury. So I think of course he is not 100% fit. He is not 100% fit. But he can play."
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