Mourinho said that he had to give the 29-year-old playing time to prepare him for the remaining two games as Fellaini missed United's last three league games after picking up a red card in the Manchester derby in April.
"Winning the Europa League would be very special". That would happen overseas. "We're not going to influence anything one way or the other in terms of results for ourselves, and it would have been a good gesture by the Premier League to have done it to give them the best chance".
Mourinho has now revealed that he intends to play third-choice goalkeeper Joel Pereira against Crystal Palace on Sunday, while Sergio Romero will be selected for United's Europa League final against Ajax on May 24. I hope you don't kill me when you see my team.More news: Senate committee wants Comey to testify
Having played several other fringe players against Southampton, Mourinho said the understudies had given him food for thought as he considers his team for the final.
"I'm happy we played like that because they know this match didn't matter, counted for nothing, so I give them credit", Mourinho said of his team. "But my team want to play at Old Trafford - they don't want to be left out".
"Any teams have a debrief at the end of the season and this is normal but the end of the season is after the last game and the last game is very important".More news: Codemasters announces F1 2017 game release date, classic cars
"I don't go with [Romero can replace De Gea] "if he leaves" because I hope he doesn't".
United manager Jose Mourinho has already said Romero will start in the final ahead of regular goalkeeper David de Gea, as he has done throughout the European competition. They want to finish off at one of the best venues in football.More news: Patients die more often with older doctors
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