Defenders Wayne Bridge, Adam El-Abd and Marcos Painter missed Saturday's 3-0 defeat at derby rivals Crystal Palace while midfielder Andrea Orlandi suffered a suspected broken rib.
And to add to manager Gus Poyet's problems, centre-half Lewis Dunk will be suspended following his early red card at Selhurst Park.
"Marcos Painter suffered a small tear in his calf during the week and we expect him to be out for two to three weeks, but you can never be sure nowadays," said Poyet.
"Wayne Bridge and Adam El-Abd were not ready so I could not play them, then when we needed a little help from Orlandi he had to go off injured. We think he has broken his rib.
"Wayne has the best chance of being ready for Saturday so we need to hope that the medical staff can produce something special this week.
"Unfortunately it's mainly the defenders who are injured and we need people to stand up now. We have a week to go until the next game and we need to relax and be ready."