United lost 1-0 to Chelsea on Saturday.
Question marks have grown over the Portuguese manager's tenure after the Old Trafford side went a season without a trophy.
Metro reports the 55-year-old spent less than 10 minutes in the changing-room with his players who were expecting a grand speech.
However, instead they were left deflated after Mourinho used the time to mainly thank the players and wish them well ahead of their holidays and World Cup plans.
To sour things further, the two-times Champions League winner refuse to return to the team hotel in London with staff and players.