Having initially been penalised for foul in his own box, Fernandes saw a penalty for the visitors overturned before the Reds were handed a spot-kick at the other end.
The Portuguese's first effort was saved by goalkeeper Sam Johnstone but VAR ordered a retake after replays showed the former United was well off his line when he made the stop. Fernandes stepped back up to convert his second attempt with aplomb and seal an important three points.
You can watch the highlights from the game at the top of this page and scroll down to see post-match reaction from Ole Gunnar Solskjaer and the players.