"I have to give some minutes to everyone because we only have 15 players. We don't have more. We only have 15," said Mourinho, who confirmed Eric Bailly is likely to feature in all three after his red card against Celta Vigo.
"So I have to play them but I have to play them mixed. I have to play them by periods and I don't have another solution.
"In the Premier League we can only finish fifth or sixth. I don't think we can finish seventh or finish fourth. So we can finish fifth or sixth and we can win a trophy.
"By winning that trophy we can play Champions League next season and that is the game.
"We are not saying matches are not important. Matches are important but we have one that is more important than others."