Jack Ross would like to add another striker to his squad but does not think it is financially viable at this stage.
Sunderland have suffered a blow this week after the initial prognosis regarding Charlie Wyke's injury proved to be optimistic.
The centre-forward, who was Sunderland's marquee signing this summer, will be out for three months after colliding with Burton Albion goalkeeper Dimitar Evtimov last Saturday.
Ross said: "It'll be Christmas/New Year by the time we see him back.
"He's been unfortunate because it's the same injury but not any relation to the fact that he had the same injury before. It's just really bad luck that it happens to be on the same leg. It doesn't require any surgery but he'll be in a brace for the next few weeks and then it becomes a process of rehabilitation.
"It's not great, I feel for him because he's never really been fully fit since he came here, he was just building up to it. He was brave in how he got the injury which probably makes it even sorer.
"Speaking to the medical staff it's not even so much the impact, it's more that he's hyper-extended because of the force. It's just an unfortunate set of circumstances."
It leaves Ross low on numbers up front, with Josh Maja and Jerome Sinclair his only other recognised centre-forwards.
Ross had explored the possibility of adding another striker earlier in the summer, even taking Polish striker Kacper Przybylko on trial.
However, he admitted last week that the ongoing stand-off with Papy Djilobodji and Didier Ndong had brought an end to his hopes of adding another trialist, defender Gael Andonian, to his squad.
The situation, Ross believes, is unchanged.
"It would be nice [to add another striker] to but I don't think I'll be able to.
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"I said just before the window that I wasn't in a position where I could bring anybody else in and I haven't had anything to suggest that it is any different [now].
"That may adjust over the coming weeks, but obviously we'd be limited to free agents.
"I've always taken the approach that it's not about complaining about what I don't have, it is about making the best of what I do have and all I can affect is getting the best out of the ones who are available, making sure that we're in a decent position when Charlie does become available again."
It is unclear whether developments regarding Djilobodji and Ndong would change that situation (Djilobodji has since been served notice on his contract), but Ross says he will simply focus on getting the best out of the players he does have available.
"It just narrows our options, whether before a game or during it, that's the downside," he said.
"It means we're a bit restricted in our options and if you're being pessimistic then if we lose another forward player, then we're very narrow.
"On the flip side, if Charlie had been with us since the start of the season and scored every week, we would be sitting saying 'it's a hammer blow'.
"It's still a blow, he's a good player and we haven't seen the best of him, but we have proven that we can win games and pick up points without him. That's what we have to do.
"Aiden [McGeady] working his way back to full fitness and Duncan [Watmore] getting closer does mean we will have options.
"We don't have a like-for-like replacement but that means I'll have enough to try and make the best of it."