Ronaldo out of Cup final, Ancelotti confirms
The Portuguese star has missed Real's last three games due to the problem and Ancelotti said he didn't want to risk him with their Champions League semi-final, first leg against Bayern Munich just a week away.
"Cristiano is not available because we don't want to take risks and we have other very important games to come this season," he said at his pre-match press conference on Tuesday.
However, Madrid have lost only once in 10 games without Ronaldo so far this season and Ancelotti believes the likes of Gareth Bale, Karim Benzema and Angel di Maria can compensate for the loss of the former Manchester United man.
"We have many players out, not just Cristiano, but we have a lot of confidence in this team and the team has always responded well to missing players. I am sure it will be the same tomorrow.
"We are going to lose a player with an incredible quality, but his absence as been provided motivation for the team to run more and play more as a team."
Barcelona have emerged victorious in both meetings between the sides so far this season, including a remarkable game at the Santiago Bernabeu just under a month ago which ended 4-3 to the Catalans.
However, Barca have endured a tough week as they were dumped out of the Champions League by Atletico Madrid before losing significant ground in the title race with a shock 1-0 defeat Granada at the weekend.
- 'Courage and personality' -
And Ancelotti believes his side must be brave and challenge Barca's authority in possession if they are to win the Cup for a 19th time.
"It is a final and we are not planning to try and stop them. We want to play with our quality, our identity. We have tried to do that all season and that is the only way we can win the game tomorrow.
"I think Barcelona are a team that continues to attack well, they had a lot of control of the ball in recent games and it is clear that is the strongest part of their game. To stop them doing that we have to have more control of the ball.
"A quality of our team is to control the game with possession and efficient possession. We need courage and personality, which are the two most important qualities for a final."
Madrid captain Iker Casillas also insisted he wasn't reading too much into Barca's form of late, given their ability to find their best form when it matters most in recent seasons.
"Personally, I don't place confidence in what Barcelona have done over the last month. This is a completely different game for them and us. In a final anything can happen."
Madrid are also likely to be missing Brazilian full-back Marcelo as he too recovers from a hamstring strain, but Sergio Ramos overcame a neck injury to train on Tuesday and is expected to take his place in the heart of the defence.
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