The Gelsenkirchen club have demanded 8 million euros for the USA forward.
According to Sport BILD, Schalke 04 have set an 8 million euros asking price for Matthew Hoppe.
The USA striker, who just recently won the Gold Cup with his country, is expected back in training on Friday.
Per the report, clubs from England, Italy and Russia are said to have already enquired for the 20-year-old.
Hoppe has a contract at 'Die Königsblauen' until June 2023 and his market value is around €4.7 million according to Transfermarkt.
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