Mark Warburton insists the financial gap between Rangers and rivals Celtic is important but they must close it quicker than Graeme Souness' target of five years.
Souness has told Sky Sports News HQ that Rangers are five years behind Celtic and must invest more in the playing squad if they hope to catch up, after they were beaten by their Old Firm rivals in the Scottish League Cup semi-final on Sunday.
But Rangers boss Warburton stressed it would be foolish to spend recklessly and not build solid foundations after the club spent the best part of a decade in financial turmoil.
"Graeme is a very knowledgeable football man steeped in knowledge of the game and of Glasgow," Warburton said. "You have to respect his opinion.
"There's a financial gap that appears at this moment, it's there for all to see. Graeme is acknowledging that, with his experience. He knows what it's like.
"But it has to be shorter than five years, in my opinion. I'm not disputing the fact that Graeme is a very smart man. I am not for one second going to ignore his opinion. But our job has to be to move quicker.
"Will the Rangers fans accept five years? I don't think so. I hope they know we are on a project, on a road, and hopefully we are making good progress down that road. But the fans have to see progress.
"The worst thing Rangers could do is spend recklessly to try and close that gap too soon. We know it's there, which is important. But what's also important is dialogue and communication within the club, and the target-setting to know what we have to do within a timeframe to close that gap."
Celtic and Rangers' summer recruitment has been widely compared and scrutinised in the Scottish media and Warburton pointed to the difference in wages that each club can offer as a factor for the gap between them.
He said: "I read some ludicrous comments this morning that my city background should make me aware of the power of financial muscle.
"I'm not a rocket scientist but I'm not a fool. Of course we recognise the implications of a rival club with a stronger financial base at this moment in time.
"You have to look at our players. I am never going to be derogatory about my players. I have been delighted with them. But we signed Clint Hill on a free, Lee Hodson on a free, Matt Gilks on a free, Niko Kranjcar on a free. I can go forward from there.
"Scott Sinclair and Moussa Dembele are two quality (Celtic) players but I don't think certain wage levels compare at this moment in time. We are working to build the club on solid foundations."