United and Chelsea were both in midweek Champions League competition، with both being held by La Liga opposition.
The Red Devils ground out a goalless draw on the road at Sevilla، with Mourinho's side having now won just two of their last five fixtures - with Huddersfield the only side to have been overcome in league and FA Cup competition.
The Blues، meanwhile، played out an entertaining 1-1 draw with Barcelona in Europe، with there plenty of encouragement to have been taken from that display. Conte's side appear to have overcome the wobble which saw plenty of uncomfortable questions being asked at Stamford Bridge، although they have still not won on the road since January 20.
Old Trafford would be an ideal place to get back on track، with United vulnerable during a run which is seeing them complement continental action with key domestic dates against the likes of Chelsea، Liverpool and Brighton.
Mourinho will be aware of how important momentum is at this stage، with there the promise of as many fireworks off the field on Sunday as there are on it as the Portuguese prepares to lock horns with his former club and old adversary Conte.