The 21-year-old was strongly linked with a move to Liverpool during the summer transfer window.
Reports even suggested that the young defender already had agreed a deal subject to a medical, but a move failed to materialise.
Schalke are reportedly prepared to sell Papadopoulos for around £11million in the January transfer window.
Manchester City, Chelsea, Inter Milan, AC Milan and Zenit St Petersburg are all reportedly keeping tabs on Papadopoulos ahead of January.
