Sunderland skipper Lee Cattermole is facing several weeks on the sidelines as he attempts to shake off a knee injury.
The 24-year-old midfielder will miss the Barclays Premier League clash with Fulham at the Stadium of Light after having an injection in the knee, with manager Martin O'Neill admitting surgery may be required if that does not solve the problem.
Full-back Danny Rose is expected to return to training next week after aggravating a hamstring strain which has been treated at parent club Tottenham.
O'Neill is desperate to tie-up keeper Simon Mignolet on a long-term contract.
The 24-year-old this week moved to reassure O'Neill that he was happy on Wearside after agent Guy Vandermissen hinted he may have to leave for a higher-profile club if he is to achieve his ambition of replacing Thibaut Courtois as Belgium's first-choice goalkeeper.
O'Neill, who celebrates his 61st birthday today, revealed talks over an extension at the Stadium of Light are under way despite Mignolet having two years of his existing deal still to run, and the Northern Irishman is determined to resolve that situation as quickly as possible.
He said: ``We would really like to try to tie him down to a longer contract. There have been talks about that for some time, but I think we would really want to try to firm that up as soon as we could.
``I think he's receptive to it.''
Mignolet has arguably been Sunderland's best player in a testing Premier League campaign to date, and the fact that he acted swiftly to silence the alarm bells will have come as a relief to O'Neill and the club's supporters alike, although the former was relaxed about the whole situation.
He said: ``I hadn't been made aware of it at all and he came up to me to tell me that he thought there was something lost in translation.
``The agent who was working in the office had made some comment about it and really, if you think about what he said - I haven't seen it first hand and therefore, it's unfair of me to make a comment - but if the gist of it was that Atletico Madrid are a better side than Sunderland, well I am not so sure that too many people would disagree with that.
``I haven't a major problem with that. Our job is to try to make us at some time or another as good as them.''
Fulham's Simon Davies has overcome a knee injury and could play his first game in almost a year.
Fellow midfielders Kerim Frei and Kieran Richardson have recovered from their respective pelvis and calf injuries but Mahamadou Diarra (knee) is out.
Young midfielder Buomesca Tue Na Banga and Ajax loanee Eyong Enoh are also available after knee injuries.
``Simon Davies is back, he is fit,'' boss Martin Jol said.
``I have to make a decision (on whether he features). I have a lot of players now but it may be about having him in the squad.''
Davies is one of a number of Fulham players who are out of contract at the end of the season.
Jol has challenged the 33-year-old to prove that he deserves a new deal.
``We like players to be quite productive,'' the former Tottenham manager said.
``He was injured probably half of the time, maybe more, but hopefully he can stay fit now.
``I have an idea that he can still prove himself again because that is what he did in the past.
``In the past he was a big player for Fulham.''