Chelsea have allowed Baba Rahman to join Schalke on an 18-month loan deal.
The Ghana international has been sidelined since he injured his knee ligament in February's Africa Cup of Nations and has not featured for Chelsea all season.
He spent the first-half of last season at the Bundesliga club before suffering the knee injury.
The Blues confirmed his switch on their website, stating: "Baba Rahman has today joined Schalke on loan until the end of the 2018/19 season."