The Portuguese has been carrying a knee injury in recent weeks, but Ancelotti has confirmed that the forward is "physically fine" for the European clash at the Bernabeu.
"He's physically fine, both his knee and his injury," he told reporters at a press conference. "I see him relaxed and eager to play. Last Saturday's booing is forgotten. He's raring to go, as always".
Ronaldo has scored 44 times in 40 games for Madrid this season.