Daniel Farke will be without Todd Cantwell, Jordan Hugill and Kenny McLean for at least the next few weeks.
Cantwell was a late withdrawal from the Norwich City squad ahead of the Middlesbrough match and Farke revealed the midfielder will miss the next three weeks of action with a hip injury.
Hugill was taken off at half-time during the victory at the Riverside Stadium and Farke admits the striker may need surgery as a result of his fall.
"It's a shoulder ligament injury for Jordan Hugill. We will try to handle this in a conservative way. He may need surgery, so that will mean a long-term absence. But he's definitely out for three weeks.
McLean arrived back from duty with Scotland in the international break for a cameo display on Saturday and the load on seems to have had an effect.
"Kenny McLean is also out, we scanned him this morning after he twisted his knee and he has a meniscus tear. We will wait for the injury to settle down and he'll see a specialist this week. We will also handle this in a conservative way.
"He will be out for six weeks or if he needs surgery it could be four to five months."
Lukas Rupp is also a doubt for visit to the bet365 Stadium with a hamstring problem.
Xavi Quintilla is still struggling with a hip injury and Farke admitted he may have to be sent back to Villarreal for a further look at the problem.
Elsewhere, Under-23s players Tyrese Omotoye and Andrew Omobamidele are both injured and won't feature in the matchday squad.