Manchester City reportedly have a £60m buy-back option on Rabbi Matondo, who left the Premier League champions for Schalke 04 during the January transfer window.
Matondo, 18, rejected the opportunity to sign a new deal with City in favour of moving to Schalke.
The teenager, who is a senior Wales international, has already made his Bundesliga debut for Schalke, appearing as a substitute in their 2-0 defeat to Borussia Monchengladbach earlier this month.
According to Football Insider, City insisted on inserting a buy-back option into the deal that took Matondo to Schalke, and the Citizens will be able to re-sign the winger for £60m.
Another former City youngster, Jadon Sancho, has forged a successful career in Germany with Borussia Dortmund.