Real meet Villarreal at the Ceramica after going to extra-time and penalties in their Champions League round 16 triumph against Atletico Madrid on Wednesday night.
Ancelotti said on Friday: “We're still recovering. Barely any time has passed since our last game and not everyone has recovered. We'll be better shape tomorrow. It's something we have to consider in preparing a game against very tough opposition. We'll have to play a smart game if we want to win it.
“We have to put in an extra effort. We won't have the usual freshness, because we haven't had enough time, so we'll have to show quality, a good attitude, and be smart about it. There's not only one way of winning. We have to play a smart match.
“I don't understand it, but we can't do anything about it. We have to play the match. The minimum recovery period should be 72 hours. It's the schedule we have, I hope that one day we can change it."
He also said: “We haven't stopped playing every three days since January. It's the middle of March now and it's too much for me even, and I'm not playing. There's no time to recover from the pressure of the games, but there's nothing I can do about it.
"The only way to put an end to it is to stop, but I don't want to do that because I enjoy what I do. The less important things are prioritised, like TV rights, money... The players' recovery and risk of injury is an after-thought."
Meanwhile, Ancelotti also welcomed Raul Asencio's first call-up to the senior Spain squad.
“We celebrated it, it's great news for him. He deserves it for the work he's doing and the discipline he's shown since he came in. He's done a fantastic job and been very committed. I hope this is the first of many call-ups for him."