The 30-year-old has endured a hard relationship with United supporters at times but has become an influential player under the Portuguese.
The Belgian international's current deal runs out in the summer and although talks regarding an extension have been ongoing, an agreement has yet to be reached.
Considering how much José Mourinho appreciates Fellaini, it would be surprising if the Red Devils didn't at least try to convince him one last time before January with a new deal.
When asked if there was anything he could do to turn it around, the United boss added: "Nothing. "(I have done) nothing, it is a discussion between the player and the board. I'm not involved in contracts, in deals. The player because he has the right to decide his future.
"I respect both the players and the board".
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Cantona, 51, described the Red Devils as "very special" and admitted he would "sit around the table" if an offer was available. "I love Pastore", he told United centric YouTube channel FullTimeDevils .
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"I just wait, wishing they will have an understanding, but it's out of my control". Along with Galatasary, Turkish giants Besiktas and Serie A duo AC and Inter Milan have all been credited with an interest in the midfielder, while Ligue 1 leaders Paris Saint-Germain have made a "concrete approach" to Fellaini ahead of a prospective summer switch, according to Le10 Sport.
"They're not back. The evolution was not good enough to have him back for the game. There is no more injury in the frame but fatigue, maybe a player that played his first match maybe he feels it a little bit".
ERic Bailly and Phil Jones will miss out againts Brighton, while Zlatan Ibrahimovic will again be on the bench. "I know we have a good record at home and are strong at home but the opponent is going to be hard for us".
United are second in the Premier League behind rivals Manchester City, who are eight points clear at the top and unbeaten after 12 league matches.
"We cannot think about the gap, we can not think about the gap to City, to the fifth position, we just have to focus on ourselves and in matches".