Kaka was handed a rare start in the absence of the injured Cristiano Ronaldo.
Mourinho remarked: "Kaka was one of our best men when we had a full lineup. He gave a fantastic performance. I'm very satisfied because he created room and covered a lot of ground. Cristiano Ronaldo told me he wasn't fit at 14:00.
"He said he could help, but that he wasn't in optimum form, that he didn't evolve as expected since yesterday. He wasn't ready to play and he didn't train yesterday."