Kagawa played in the playmaker role in the second half after replacing Juan Mata, having also been used as a holding midfielder in the previous two games.
"I know him from Borussia Dortmund and he played in the no.10 position," van Gaal said.
"I wanted to try him in the no.6 or no.8 position in our system in the first two matches, and then I also gave him a chance at no.10 because he wanted to play in that position. He did it much better than in the two matches before."
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