The 18-year-old midfielder currently holds the title of Asian Young Footballer of the Year, and is widely regarded as a star of the future.
Now, sources in Japan claim that the reigning Premier League champions have firmed up their interest in Ishige, by giving him the chance to impress Manchester City coaches when he arrives at Carrington.
His current manager Afshin Ghotbi, was full of praise for the talented teenager, adding that he would not stand in his way, should he decide his future would be better served in England.
"If you want to build top players you have to give them the opportunity to gain experience," he said.
City are notoriously big spenders in the transfer market, but had a relatively quiet window by their own standards last summer. It would seem the club are actively trying to change their tact, by recruiting up-and-coming talent with UEFA's Financial Fair Play guidelines on the horizon.
Ishige would represent another value-for-money acquisition, as Mancini looks to nurture another prospective talent and protect the club's long-term future.