#4 Fred

The Brazilian came to United from Shakhtar Donetsk with quite a reputation. United managed to snatch Fred in spite of interest from their local rivals, Manchester City. His ability to run with the ball, technical prowess, and the box to box nature of playing had United fans excited to see him in action.
But thanks to a poor start in Premier League, he finds himself either on the bench or out of the squad. José Mourinho has pointed out defensive frailties as the possible reason for the snub. Be it his own form or the defensive frailties Manchester United find themselves in, either way, Fred so far does qualify as a flop signing under Jose Mourinho. The only positive, however, is that he is only 25 years of age and still has a lot of time to prove himself.