The midfielder will remain in Germany during the international break having been forced off during Schalke's 4-1 Bundesliga win over Augsburg on Saturday. A decision will be made next week on whether he will be fit to return to club action against Eintracht Braunschweig on Oct. 19.
A statement on Schalke's website confirmed he will undergo "intensive conservative treatment" in order to "improve the state of irritation in the left knee."
Schalke has lost just once in all competitions since Boateng arrived from San Siro, with the former AC Milan man scoring four times since his summer move.
Ghana faces Egypt in the first leg of their World Cup playoff Tuesday, before the return leg Nov. 14.