The Red Devils were held to a 2-2 draw by bitter rivals Arsenal at Old Trafford after Manchester United came from behind in both the first and second half to secure a point.
Manchester United are languishing in eighth place in the Premier League table and eight points adrift of fourth-placed Chelsea FC in the race to secure a Champions League spot.
Mourinho led Manchester United to their best finish in the post-Sir Alex Ferguson era with Faria at his side last term after the 20-time English champions ended up as runners up behind Manchester City.
Ex-England international Michael Carrick has replaced Faria alongside Mourinho on the Manchester United bench this season as the Red Devils continue their alarming slump.
Faria met Mourinho during the latter’s time at FC Barcelona as assistant manager and the 43-year-old was by the Portuguese manager’s side at FC Porto, Chelsea FC, Inter Milan, Real Madrid and Manchester United.
The pair have won eight domestic titles, the Champions League twice and the Europa League to underline their successful working relationship.
Former Manchester United midfielder Scholes believes Faria’s exit at the end of the 2017-18 season is a big blow to Mourinho.
“I think the assistant (leaving) is the big one,” Scholes told BT Sport. “Rui Faria was with him for a long time, he had been at every club with him.
“All of a sudden he is gone and apparently, I don’t know, but apparently he was very influential in what he did day to day. He’s lost that and he (Jose Mourinho) does look a bit lonely at times. I think that’s a big part of it.”
Manchester United will welcome Fulham to Old Trafford on Saturday evening.
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