Real thumped Celta 6-0 on Saturday.
Zidane said: "I don't know my team yet [for the final] but it's better to have everyone plugged in. Then, of course, it will be a headache to select the team for the final. We had a great game and that was important. We were very professional, scoring six goals and playing a lot of football. We did very well."
On Bale's showing, the coach added: "He is very good, he has shown that. He was good at everything tonight. I am happy for him. But the important thing is that we all arrive in optimal form."