David Wagner revealed Elias Kachunga will be out a few weeks after suffering an ankle injury in the 1-0 defeat at Newcastle.
Kachunga went off after 56 minutes at St James’ Park after a heavy challenge from Brazilian winger Kenedy.
“Unfortunately he has an ankle injury and it looks like he could be ruled out for a few weeks,” said Wagner, who had included the German-born star among five changes to the starting line-up.
“We have to make further investigations but the ankle doesn’t look nice.
“It was a harsh tackle and there is big swelling on his ankle so we expect a more serious injury.”
Kachunga had previously been sidelined with a knee injury sustained at Watford in December, with the St James' Park outing his first start since taking to the turf at Vicarage Road.