Schalke 04 have demoted Hamza Mendyl to the U23 team for disciplinary reasons with no date set for his return to Huub Stevens' squad.
The left-back joins Algeria's Nabil Bentaleb in the youth team and will miss the Royal Blues' home fixture against Eintracht Frankfurt on Saturday.
Mendyl joined Schalke 04 from Lille last August for an undisclosed fee and has rarely featured for the Veltins-Arena outfit who are 14th in the German top-flight log.
The Casablanca-born defender who has played nine league games so far this term last appeared as a 74th-minute for Schalke in their 7-0 defeat to Manchester City back in March 12.
Though his offence was not stated by Huub Stevens, the gaffer assured that the 21-year-old would be given another chance to redeem himself.
"Everybody gets a second chance. Hamza Mendyl is currently training with the U23s for disciplinary reasons, but the door is always open for a return," Steven said.