United responded to the Liverpool result by winning 3-0 at Tottenham but have since scrambled a late draw at Atalanta in the Champions League and been comprehensively beaten by Manchester City and a struggling Watford whose only previous home league victory came on the opening day against Aston Villa.
"Watford away from home, you need to give them a harder time than we did. They outfought us, we allowed them to put the ball in our box too easily. There are so many things that can go wrong in football and too many did in the first half."
De Gea, who saved a twice-taken penalty from Ismaïla Sarr early on, could not hide his disappointment. "It was embarrassing, the way we played today," he said. "The first half was very poor, it's not acceptable for this club and the level of players that we have. It's another nightmare. There's been some difficulties but I don't really know what to say.
"I have been in difficult moments with this club but we are in a difficult situation. We don't know what to do with the ball, we are conceding a lot of goals. It's a horrible moment."
