Steve Bruce insists he will not spend the sum received for selling Darren Bent in January, but has acknowledged an interest in Stoke City striker Ricardo Fuller.
Bent left Sunderland for Aston Villa earlier in the week and the England international striker's sale brought in an initial £18million.
Black Cats boss Bruce is looking to bring in a new forward to replace Bent, particularly after the on-loan Danny Welbeck was ruled out for up to two months after knee surgery.
However, Bruce has moved to dampen supporter expectations that he could sign a big-money replacement for Bent during the current transfer window.
"I have to tell all the Sunderland fans if they think I am going to go out for a marquee signing and spend £20million, it's not going to happen," said Bruce.
"We have got to look and make sure we are patient and hope. I will try to bring in a couple of bodies that will help us in the short term, and look to go again in the summer.
"We are looking, we are looking, but it is like puppies at Christmas - you don't just go and buy one for the sake of it because they do need nurturing and looking after after a while.
"We will make sure we try to do our homework. We have got a couple of irons in the fire and we will bring the right people to the club."
Sunderland are perceived to have cash, even though as with most transfer deals these days, Villa's payments for Bent will be staggered and Bruce insists he will not be held to ransom.
He said: "Of course, people will try to take my pants down and try to give me a smacking, but we will be okay with that.
"I am sure people will try it on, but I'm a bit long in the tooth for that."
Skysports.com revealed on Thursday that the Black Cats are considering a move for Fuller and Bruce suggested the Stoke front-man is one of his targets.
He continued: "To be fair, we are putting the net far and we know there are certain individuals who could be available.
"Ricardo Fuller could be one of those, but we have got the irons in the fire, four or five as we speak.
"I like Ricardo Fuller, I think he has been a very good player in the Premier League, and we will see.
"Just watch this space for the next 24, 48 hours."
What will be the outcome in the match Blackpool vs Sunderland?