The Gunners travelled to Old Trafford with not much on the line for them in terms of the league and played a rotated side.
United scored first through Paul Pogba after some bright play from Alexis Sanchez and Romelu Lukaku but Arsene Wenger’s men grabbed an equaliser after the break.
Mourinho brought on Fellaini as he often does as his plan B option and it worked once more with the goal seeing the match end 2-1 in Old Trafford’s favour.
The goal was scored in injury time to send fans into ecstatic celebrations but more importantly it meant another three important points in the race to secure second place.
There’s no doubt that Marouane is more dangerous in an opponents box than he is at protecting his own team’s box and his efforts have paid off.
With reports that the Belgian is set for a move away from the Red Devils in the summer, Jose may have to begin to consider a new kind of backup plan.
The former Everton man’s contract ends at the end of the current Premier League campaign and he appears to be allowed to leave for free.