Manchester United suffered their third defeat in a single week after Watford earned a deserved 3-1 victory on home ground.
Watford took the lead after 34 minutes; Etienne Capoue sidefooted a Daryl Janmaat pass in the United box past David De Gea’s outstretched leg.
It was not until after half-time that United managed to a reply. Marcus Rashford scored even as he missed a header, and made no mistake on the follow-up to finish from close range.
As the game looks headed towards a draw, Watford substitute Juan Zuniga, who came on for Capoue, scored a first-time curling shot across De Gea and into the far corner.
The game was taken out of United hands after Marouane Fellaini fouls Zuniga in the box, with Troy Deeney smashing in the ensuing penalty emphatically.
United’s defeat at Watford follows up the Red Devils’ loss to neigbours Manchester City and a shock disappointing Europa League defeat by Feyenoord.
Club manager Jose Mourinho believed that some of his players could not cope with the need for competitive wins.
“I feel that some individuals probably feel the pressure and responsibility too much,” the Portuguese said. “We have to improve, no doubt, individually and collectively. And that’s my job.”
“We started the season very well with winning the Community Shield and three victories in a row in the Premier League, the best start that a new manager has had at Manchester United I think. But was I thinking that my team was ready, perfect, unbeatable? Not at all.”
“I was completely aware that we were not perfect, with lots of players who are not end products and can make their own mistakes.”
Nevertheless, there is little time for United to breathe or lick their wounds as they prepare to face Northampton in the League Cup midweek, and defending champions Leicester City next weekend.