Kaka was preferred to Mesut Ozil on the night.
Mourinho said: "Kaká was a starter and Özil a substitute, it is not something definitive. I felt that with his game, the opposition and the work he has done during the week it would be good for him to play against Ajax. The press thinks that every time a high status player is on the bench that it is a big problem, my job is think of those who will play and get the best performance. I have to choose eleven players and there is always someone who gets left out."