After midweek defeat to Feyenoord followed Manchester City's triumphing in the first Manchester derby, Jose Mourinho needs a win to escape a potential rut for his new Manchester United side.
Not only that, but a stand-out performance from world-record signing Paul Pogba is also required to silence a whole host of critics following average performances nearing on poor against both Feyenoord and City.
The requirements are a plenty for Mourinho and United despite it being early in the season, with pressure high following a seventh consecutive win for their local and competitive rivals City.
Watford, meanwhile, come into this game in very different circumstances. The pressure on the Hornets is minimal, particularly after a sensational comeback away from home to West Ham United last weekend, winning 4-2 having been two goals down. Goals from Odion Ighalo and Troy Deeney saw Watford go into the break level, but they didn't lose momentum at that point as Etienne Capoue and Jose Holebas scored a third and then a fourth to give them a remarkable and unlikely three points.
Another advantage for Walter Mazzari's side is they haven't played since last Saturday, whereas United only returned to England from Rotterdam on Thursday night following their loss to Feyenoord.
Stefano Okaka is likely to be the only player unavailable for Walter Mazzarri, who has insisted he no longer has any kind of feud with his opposite man Jose Mourinho. Okako is still recovering from a hamstring injury.
Both Younes Kaboul and Sebastian Prodl should recover from knocks in time to play on Sunday in the early 12PM kick-off.
Henrikh Mkhitaryan remains sidelined for the Reds, continuing a poor start to his United career after joining from Borussia Dortmund for almost £30million. He should, and will certainly be hoping to, come back to the squad for United's league game against Leicester City next weekend.
Luke Shaw was substituted in the Manchester derby following a slight hamstring injury but did not travel with United to Feyenoord and is expected to have recovered in time to start at left-back on Sunday. Eric Bailly did travel to Rotterdam and suffered a knock. He continued playing with it, and so should be in a position to start against Watford, too.
The only long-term injury is defender Phil Jones, not entirely surprisingly either. The Englishman has picked up yet another injury, this time a knee ligament injury in training.