Faria was by Mourinhos side for the very last time as United succumbed to a 1-0 defeat to Chelsea in the FA Cup final on Saturday, and will now pursue his first managerial role.
Mourinho has already handed Michael Carrick a coaching role, and now The Times report that Italian fitness coach Stefano Rapetti will also join the new-look backroom team too.
Mourinho does not believe any one coach can come in and replace Faria, who has worked under Mourinho since his very first job in charge of Uniao Leiria.
Instead, Mourinho wants three coaches to take on Farias old responsibilities: Carrick will work directly under the United manager, while Rapetti will predominantly be in charge of fitness and physical conditioning.
Mourinho also wants a third tactics coach to complete his staff and has been keen to surround himself with people he already knows, with Rapetti having worked under the Portuguese boss at Inter Milan.
He was promoted to the first-team coaching staff while Mourinho was in charge at the San Siro and is currently at Sampdoria after a spell at Empoli.
Sampdoria take on SPAL in their final Serie A match of the season on Sunday, which will be Rapettis last day at the club with United already having agreed a deal to bring him to Old Trafford.
Speaking about replacing Faria previously, Mourinho explained: When Rui is leaving after 17 years I have nobody, nobody in the world of football ready to be my assistant manager. Nobody.
So I prefer to educate people, to structure my staff in a way where there is space for their education, for their improvement. But obviously Im going to improve my staff in the performance level related to the fitness and the relation with the tactical work.
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