#3 Defensive disarray
Manchester United like each one of Jose's sides have been brilliant defensively. They boast the best defensive record in the league where they have only conceded 19 goals so far.
The headache for Mourinho, however, is the frailty of the duo of Smalling and Jones. In their pairing, United have two centre-backs who are heavily undependable. Eric Bailly's absence has exposed the disorder in the United back-line.
Moreover, Pogba's forward venturing runs have left Nemanja Matic exposed in front of the back-four who also appears to be rusty at the moment.
Forget the Champions League, the lower league opponents like Wigan in the FA Cup capitalize on the slightest of errors committed by their counterparts.
In such a scenario, even hopes of lifting the FA Cup might seem far-fetched. Jose needs to figure out a way to solve the defensive mess in his team in order to land the domestic cup.