Schalke's Dutch striker Klaas-Jan Huntelaar is an injury concern for Wednesday's UEFA Champions League play-off, first-leg tie at home to Greece's PAOK after injuring his right knee.
Huntelaar, who scored twice last weekend in the 3-3 draw at home to Hamburg, injured his knee in a clash with Wolfsburg goalkeeper Diego Benaglio as Schalke lost 4-0 on Saturday in the Bundesliga.
"I took a blow on the knee and now must wait and see what the X-rays show in the hospital," Huntelaar, who has scored 49 goals in 84 league games for Schalke, told German magazine Kicker.
Following a goalless first-half, the 30-year-old Huntelaar failed to come out after the break at Wolfsburg as the hosts ran riot with four unanswered goals.
After Metalist Kharkiv were thrown out of the Champions League for match-fixing last week, PAOK replaced the Ukrainains in the play-off.
The first leg is at Gelsenkirchen's Veltins Arena next Wednesday with the return leg in Greece the following Tuesday.