Mourinho, who made five changes to his line-up after Wednesday's win over CSKA Moscow, added: "I could see the difference between Henrikh Mkhitaryan and Fellaini".
However, there is rather more depth and stability to Jose Mourinho's squad.
Palace are now only the second Premier League side in history to lose their opening seven games - after Portsmouth in 2009-10 - and the first in 129 years of the Football League to do so without scoring a single goal.
After a big victory in the UCL, they look to head back to Old Trafford on Saturday and score another victory as they take on Crystal Palace. As such, expect United to stay firmly near the top of the Premier League table.
United had earlier taken the lead after just four minutes against Palace when Marcus Rashford darted into the penalty box and picked out Juan Mata. This side is yet to have scored a goal all season and it is looking like they are heading for relegation unless they can pull something fantastic out of the bag very soon.
As for Crystal Palace, they couldn't come into this game in any worse form.
Left-back is a problem in this United team, with Matteo Darmian and Daley Blind finding it hard to nail down the position, while Luke Shaw remains out of favour under Mourinho.
It was the first time Fellaini has scored twice in a game for United since joining in 2013.
Liverpool, who played Spartak Moscow in Russian Federation on Tuesday, are the only team to play on Sunday, against Newcastle at St James' Park.
The absence of Pogba and Fellaini gives Ander Herrera the chance to impress alongside the impressive Nemanja Matic.
With Manchester City facing champions Chelsea at Stamford Bridge later on Saturday, United temporarily moved to the top of the Premier League as Lukaku scored his seventh goal in his last six appearances.
They haven't lost any of this season's games, including the Champions League and the Carabao Cup matches. Fans Favorite Ander Hererra will likely partner Nemanja Matic in a midfield pivot, the Spanish worldwide will be starting his second game in the Premier League this season since the 2-2 draw at Stoke.
After a trip to Chelsea comes a visit to Newcastle United on October 21, before a massive game at home to West Ham United on October 28.
"Three points and a good performance".