Schalke 04 have confirmed that Kyriakos Papadopoulos suffered a minor injury setback last weekend after stepping up his rehabilitation from a long-term knee ligament injury.
Papadopoulos is yet to feature this season as he continues to struggle with a persistent problem in his left knee, which he had an operation on last December.
The Greek defender played 90 minutes for the reserves last weekend but has since complained of discomfort in his right knee, with Schalke revealing that club doctors have diagnosed the problem as a Grade 1 lesion of the medial collateral ligament.
The 21-year-old will now rest for the next few days before resuming light training later this week, with the target still a first-team return before the Bundesliga's winter break next month.
Schalke boss Jens Keller has been forced to deal with a string of injury problems this season, with last season's top scorer Klass-Jan Huntelaar out until the new year nursing a similar injury.
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