Schalke's winning start to their Bundesliga campaign at Werder Bremen came at a cost after it was revealed that Matija Nastastic faces a lengthy lay-off with a ruptured Achilles.
The Serbia centre-back lasted just 17 minutes of the impressive 3-0 victory at the Weserstadion on Saturday before limping off and being replaced by Roman Neustadter.
The Gelsenkirchen club tweeted: "What a blow! Matija #Nastasic has ruptured his Achilles' tendon & underwent surgery this evening. Get well soon! #s04."
Nastastic, 22, joined Schalke from Manchester City on a permanent deal in June after a successful loan spell last season.
A Theodor Gebre Selassie own goal and strikes from Klaas-Jan Huntelaar and Jean-Eric Maxim Choupo-Moting ensured Schalke started the Bundesliga in style.
