The Japan international, who was sold back to Dortmund for £8million after dropping out of Louis van Gaal's plans, netted in a behind-closed-doors game between the Dortmund first team and their U23 side.
Before the game Dortmund coach Jurgen Klopp, who sold Kagawa, 25, to United in 2012, told Bild: "He actually looks good. His football game is all there, and he is still the same boy. All is well."
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