Disharmony amongst the squad
With constant contract negotiations being the talk of the training ground and players feeling undervalued or disregarded, this could lead to a squad full of bad morale and unhappiness. Which in turn, mirrors out on to the pitch if left too long, as we saw with Arsenal and Alexis Sanchez.
United have always been a well-run club and have often led by example, though could those days be over? Indeed, by leaving talks to the last minute or simply not responding to players needs, they could start to see themselves at sixes and sevens.