Steven Gerrard didn’t lose any of his key stars.
There was an expectation that at least one asset would be cashed in on after failing to reach the Champions League group stages.
The winners of this season's Scottish Premiership will almost certainly gain direct entry into next season's group stages.
Celtic, however, have sold a number of players across the past two windows.
Writing in his Daily Record column, Ferguson said: "I understand that Rangers have said they need to start moving players on and not doing so might cause a few ripples of concern among some fans especially when you see Celtic banking the best part of £40m for selling Odsonne Edouard, Kris Ajer and Jeremie Frimpong in the last two windows.
“But that figure is the minimum prize for winning the title this season because of the Champions League jackpot up for grabs.
“And Rangers have clearly weighed things up and decided that nothing which came their way in the last three months was worth gambling that jackpot on.
“I have no concerns whatsoever over the lack of a bumper sale and there’s one big reason for that - Douglas Park. I know the chairman well.
“I know the club is being run properly with him at the helm.”
Ferguson also reckons the continuity from last season means Rangers are a “step ahead” of rivals Celtic.
The Ibrox side recorded a key victory before the international break, defeating Ange Postecoglou’s men 1-0.
"Keeping their best players means they are already a step ahead of Celtic because these guys all know each other inside out now so there’s no massive rebuild required,” Ferguson said.
“Celtic on the other hand are in the midst of a massive turnaround.
“They have freshened things up and I have been impressed with some of Ange Postecoglou’s signings but I know myself how difficult it is to gel a team. It doesn’t happen overnight and Celtic have a dozen new guys to bed in. In almost every position.
“In contrast this Rangers team know exactly what’s expected, how their manager wants them to go about things and that was abundantly clear in the Old Firm victory last week."