The Gers have lost their last three fixtures at the Govan ground – against Dundee United in the William Hill Scottish Cup and Kilmarnock and Hearts in the SPL.
And if they lose to Neil Lennon's team on Sunday it will be the first time in their entire 140-year history they have been beaten in four domestic games at home in succession.
This is the worst possible time for the Light Blues to be squaring up to their city rivals; they have a horrendous injury list and their players have been forced to take massive pay cuts of up to 75%.
But Ferguson, currently in charge of Perth Glory in Australia's A-League, knows how much victory in the world-famous fixture means to McCoist.
And he is confident his old friend will – despite the possibility that Rangers could go into liquidation – be able to orchestrate a morale-boosting triumph.
He said: "There is no way that Ally McCoist will be anything other than fully focused on leading Rangers to victory in this match. There is still pride at stake and that is important.
"Yes, the club is experiencing financial difficulties at this moment in time and Ally has a lot on his heavy plate with his involvement in things behind the scenes.
"But when the Old Firm game comes along everything else will be put on the back burner.
"There is nobody prouder than Coisty when it comes to Rangers and he will be desperate to win this game.
"A lot of people are saying Celtic will win this game comfortably. Sorry, but I don't see it that way. If the players have the passion, the desire and the hunger – and Ally will make sure that they do – then they can win."