Town legend Terry Butcher believes owner Marcus Evans will eventually have to loosen the Portman Road purse strings to give the club a more realistic chance of reaching the Championship play-offs.
The Blues, currently 12th, eight points off the top six, have rarely paid significant transfer fees during Mick McCarthy’s five years-plus as manager, while their wage bill - £17.78 million in the year to June 2017 - has been around the 18th highest in the Championship in recent seasons.
"If you've only got buttons to pay, you're not going to get the quality to lift you into the play-offs," Butcher, 59, told BBC Radio Suffolk.
"Marcus Evans, sooner or later, will have to release the purse strings. Perhaps not to the extent of Wolves, but if you do buy good players and buy quality it does get you wins, it does get you goals and it does get you up the table.”
The former England captain added: ”I think there's got to be more input from the [owner].
"If Mick does go at the end of the season, any new manager is going to come and the first thing he's going to say to Marcus Evans is 'What's my war chest? How much can I spend?’.
"The manager should already be looking at signings for next year - you need that as a security and we haven't got that."
McCarthy is out of contract at the end of the season - although the club has an option to keep him for two more years - with no decision yet made on whether he will be in charge at Portman Road beyond the summer.
Speaking last Friday, McCarthy revealed he had already held talks with owner Evans about his future and said those discussions are ongoing.
Having previously indicated he might not necessarily accept a new contract if one were to be offered, McCarthy appeared more receptive to extending his time at the club, saying that there was "a good chance" he'll remain at Town if owner Evans wants him to stay.
Last week, McCarthy was the bookies' favourite to become the new Barnsley manager, a link both he and MD Ian Milne dismissed.
St Mirren boss Jack Ross is now the favourite to take over at Oakwell, the Paisley-based club reportedly having given the Tykes permission to speak to him.