The result left them eight points behind neighbours Manchester City, however the Red Devils have been massively boosted ahead of Saturday's clash with Newcastle.
Marcos Rojo and Zlatan Ibrahimovic are both available for the first time this season after severe long-term injuries, while record signing Paul Pogba is also back in the squad.
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The midfielder last played for United on September 12, where he lasted just 19 minutes of the Champions League win over Basel before picking up a hamstring injury.
Man Utd have been without the talented Frenchman for over two months, and Jose Mourinho has now explained exactly what his side have missed due to his absence.
Mourinho: What we've lacked without Pogba
Without Pogba, Mourinho believes United kept their "togetherness, organisation and discipline", however he's admitted they also lost three key attacking qualities.
Speaking on the club's 12 matches since Pogba suffered his injury, the "Special One" said, via Manchester Evening News: "We lost other qualities and we tried to get over that with Fellaini.
"But then we lost also Fellaini (to injury), and to be for so long without Fellaini and Pogba, we lost very important qualities."
Mourinho continued: "One of them was physicality. We lost a lot in relation to that. The other is the capacity to put pressure high up the pitch.
"The other is the quality of passing and the connection with the strikers. We lost a lot of qualities but we kept quiet and fighting and not bringing to the table that discussion all the time.
"We gave opportunities to other people, we gave everything we had and we had good results, bad results and life goes on."
Pogba's return is huge for Man Utd
With Pogba on the sidelines, in addition to Fellaini and Michael Carrick, Mourinho has been limited to Ander Herrera, Nemanja Matic and Scott McTominay in central midfield.
Whilst Pep Guardiola's Man City have scored goals for fun, United have struggled to create chances of late, managing just two shots on target in the defeat at Chelsea.
Henrikh Mkhitaryan's drop in form means Man Utd have been desperately lacking creativity from central areas, and Pogba possesses the technical abilities to provide that.
Mourinho will hope United's talismanic midfielder is able to put his injury behind him, supply Romelu Lukaku and perform at his best in the coming weeks, ahead of the busy festive period.
Do YOU agree with Mourinho? How big do YOU think Pogba's return will be for Man Utd? Leave YOUR opinion in the comments box below!
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