The two men, who made off towards the Woodwynd area, are both described as 5ft 7in, one wearing a black hooded top, a black balaclava and brandishing the firearm, and the other wearing a grey hooded top, black balaclava and holding the knife.
Even on Saturday, when Keane had been suckered into a red card by Jason McAteer - hardly the sharpest knife in the drawer when it comes to the game's black arts - Ferguson's first instinct was a defensive one.