Kagawa himself is yet to comment on the proposed transfer, but Zaccheroni says it augurs well for Japanese football.
"I know he doesn't want to talk about it, but I also think it's an issue you can't ignore either," he said. "I think his transfer is great not only for himself but for all football in this country.
"I've been in Japan for almost two years now and in that short period of time, two players have signed with the biggest clubs in the world - [Yuto] Nagatomo went to Inter and now Kagawa to United. It's proof the Japanese are developing players the right way."