There is some concern with a lack of preparation time for the weekend and Andreas Pereira is no longer available after his loan move to Valencia. Luke Shaw and Ashley Young have had run-outs for the Under-23s, while Zlatan Ibrahimovic and Marcos Rojo remain on the sidelines.
"We have to wait and see," the manager told MUTV, when asked for an update on the team news situation. "There is still one more training session. Not every player has reported yet, so today is the first time we are all together.
"I hope that these 15 days without us being together and working together, doesn't affect us too much," Mourinho added at his press conference. "I know it will affect [us]. I know that one thing is a week working with the players and working tactically and going through every principle of play to be ready for the weekend match; another thing is to have the players away and arriving step by step.
"I don't even see them all. Today is the first time I see them all together, and obviously today is not a day to work; today is just a day to make the decision and the selection and to travel to Stoke. But hopefully, we can keep a good level of play."
With a busy month set to unfold, the manager has revealed he will shuffle his pack and afford opportunities to all of his first-team players with challenges also being posed in the Champions League and Carabao Cup.
"The squad is strong," stated the manager. "The players are ready to play, the decision to leave people on the bench is hard, the decision to leave people at home is hard. The fact that now we play every three days, in relation to that, I think is good because the players will feel now that they are all involved.
"I think, by the end of September every player [will have] played, every player [will have] started matches because it's the normal movement of the squad and that is not a problem at all - that makes my control of my human resources better, easier and simple. But the matches are difficult and we have always the risk of being unable to keep a winning run, which is really difficult to do."