Nastasic has been forced to undergo surgery on an Achilles injury after suffering the injury in the 3-0 victory over Werder Bremen on Saturday.
What a blow! Matija #Nastasic has ruptured his Achilles' tendon & underwent surgery this evening. Get well soon! #s04 pic.twitter.com/4K1bEDpc0s
— FC Schalke 04 (@s04_en) August 15, 2015
Reports suggest Nastasic could be out of action for six months.
Nastasic joined Schalke from Manchester City on a permanent deal this summer.
