Sam Allardyce has been dealt a double injury blow in Sunderland's bid to remain in the Premier League.
Attacking duo Jeremain Lens and Duncan Watmore are both facing spells on the sidelines, with the latter potentially facing a serious lay-off.
Watmore suffered suspected ankle ligament damage in last weekend's draw at Liverpool after the 21-year-old was forced off before half-time.
And Lens - who missed the Liverpool game entirely - is struggling with a suspected hernia and will require surgery, although his lay-off is not expected to be a lengthy one.
Billy Jones is a doubt for Saturday's visit of Manchester United too with a hip problem, with Younes Kaboul definitely out after twisting his ankle last week, although the centre-half could return for the trip to West Ham in a fortnight.
"The injury to Younes Kaboul was a big blow because we'd got him fit," said Sunderland boss Sam Allardyce.
This is a different area, he twisted an ankle in training which was extremely difficult for him to take after building himself up from the hamstring injury he got at Chelsea.
"We hope that's not going to be too long.
"Duncan Watmore is again ankle ligaments, which look a bit more serious than Younes'.
"Jeremain Lens hasn't recovered like we thought he would, so we've got a clinical diagnosis to make.
"The physios think it's a hernia, but that can be repaired very quickly today though and be recovered in 10-14 days.
"If that's the case, we'll get that done.
"We have two weeks with no game after Manchester United, so that helps with the recovery of injuries.
"Come West Ham, hopefully some of these players will be back.
"Fabio (Borini) has recovered from his illness and given it to me! I'm quite happy to take that off him."
Allardyce has also confirmed that Adam Johnson will not be available for this weekend, amidst his ongoing court case.