#1 Paul Pogba
Without a doubt, the most obvious regression under Jose Mourinho at Manchester United is Paul Pogba. The record signing was meant to be a symbol of United's success under the Portuguese manager when he was signed in 2016, but things have not gone to plan.
Pogba arrived at Old Trafford in the summer of 2016 with huge expectations. The Frenchman had enjoyed four wonderful seasons at Juventus, playing 124 times and scoring 28 goals for the Old Lady, winning four consecutive Serie A titles during his time there.
His role as a midfield general at the Allianz Stadium was exactly what Manchester United had been craving for years. Not since the days of Roy Keane had the Red Devils entered a new season with a strong box-to-box midfielder who could lead his team to victory.
However, all hopes of Pogba dragging United to the Premier League title in the 2016/17 season quickly disappeared. Rather than the commanding presence witnessed at Juventus, Pogba was timid, lacking confidence, and generally very poor for United throughout the season.
Tasked with a primarily defensive role, Pogba's creativity disappeared and the Frenchman genuinely looked uninterested for long periods of matches. Last season was not much better as the 25-year-old again failed to impress on a regular basis although Mourinho did allow him to move slightly further up the field due to the arrival of Matic.
Public rifts between Pogba and Mourinho along with rumours of a move away from Old Trafford has not helped the situation moving into the new season. An attempt to vanquish talk of issues between the pair by handing the 25-year-old the captain's armband for United's opening two games is a ridiculously transparent move by Mourinho.
Pogba's performances in helping France lift the World Cup during the summer underline the player's ability when used correctly. However, it seems the Portuguese manager is unable or unwilling to do so when playing the Frenchman in the United starting XI.
Whatever happens this season, the Old Trafford faithful is yet to enjoy anywhere near the full capabilities of Pogba's talents and Mourinho is to blame.