The Red Devils slumped to a 3-1 loss at West Ham United in the Premier League at the London Stadium on Saturday evening.
Manchester United were 2-0 down at half-time before Marcus Rashford halved the deficit to offer hope of a potential comeback.
However, the Hammers restored their two goal cushion to secure their second Premier League win of the current campaign.
Manchester United haven’t won the Premier League title since 2013 when Sir Alex Ferguson was still in charge at Old Trafford.
Mourinho’s side are currently nine points adrift of Premier League leaders Manchester City and Liverpool FC.
Former Manchester United defender Ferdinand has questioned Mourinho’s side over the failure to do the simple things right.
“There will have to be questions about the manager and the squad,” Ferdinand told BT Sport.
“There have to be improvements as a team. The basics are not being done. The effort, the desire… you expect that standard but it’s not happening. Something has to be said.”
Manchester United will take on Valencia in the Champions League on Tuesday evening in search of a second successive European victory.
The Red Devils ended up in second spot in the Premier League table last term after Manchester United ended 19 points adrift of leaders Manchester City.
The 20-time English champions signed Shakhtar Donetsk midfielder Fred, FC Porto defender Diogo Dalot and Stoke goalkeeper Lee Grant in the summer.
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