Alli has been cast aside by Mourinho at Tottenham this season and the FA Cup would have been another chance to impress having started against eighth-tier Marine in the last round.
The England international was absent from the squad which won at Sheffield United last week but Mourinho said it was due to his injury.
Giovanni Lo Celso will miss the tie while right-backs Matt Doherty and Serge Aurier are both doutbs.
“The injured players that are not doubts about playing or not playing is Lo Celso, who still has a few more weeks,” said Mourinho.
“Apart from that we are talking about small injuries, question marks and doubts in that little group we have two or three players with small problems that I am not sure they can play the match on Monday.
“Matt Doherty, he was not involved at Sheffield United, I’m not sure he will recover, Dele All is not training in the last couple of games, a small problem in the tendon and Serge Aurier also is not really well. We have a few but out at this stage, still three days before the match, the only one I can say completely out is Gio.”
Predicted XI: Hart; Tanganga, Rodon, Sanchez, Davies; Winks, Sissoko, Gedson; Bale, Vinicius, Lucas