Just like a dream in start for Ferguson, as goals from Joe Wright and Brad Lyons put the home side in a commanding position after just 15 minutes.
But Rangers hit back before half-time through Vaclav Cerny’s 11th Scottish Premiership goal and equalised at the start of the second half as Cyriel Dessers nodded in a corner.
The Nigerian then put the visitors in front nine minutes later, before substitute Nedim Bajrami rounded things off with a goal in the latter stages, securing a first win in charge for Ferguson.
The 47-year-old acknowledged that his side only keep moving, after going behind, but was delighted with the fight from his players in successfull comeback win.
Faguson men remain second in the Scottish Premier League.