The Italian coach admitted after a labored Blancos performance in their Liga opener that the Portugal international and the rest of his teammates are not yet fully match fit.
Just three days after losing the second leg of its Supercopa de Espana clash with city rival Atletico, Los Blancos kicked off their Liga campaign with a lackluster 2-0 win at the Santiago Bernabeu.
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Karim Benzema opened the scoring on the half-hour mark before Ronaldo secured all three points with a long-distance drive right at the death, but Ancelotti admitted afterward that the Portugal international is still working his way back to full match fitness - just like the rest of his teammates.
"He’s not in optimum condition; but we aren’t yet," the Italian coach told reporters. "We’ve been working on the aerobic performance. We need more rhythm.
"There was some tiredness because we’ve played every three days since August 12 and it’s not easy to play every three days in the preseason. We were tired. We only played three days ago and it’s not easy to go straight back into action after that amount of rest."
The manager did see a few positives.
“Having said that though, I think we controlled the game. We’re not at our best yet. We need to quicken the game up. But I’m sure that will come with time,” he said.
Star summer signing James Rodriguez failed to shine at the Santiago Bernabeu but Ancelotti believes that the Colombia attacker needs time to adjust to a more withdrawn role.
"At the moment we’re trying James a little bit further back," the former Chelsea boss explained. "He needs to get used to it, but he’s got the quality to do it well."
However, Ancelotti added that James will be given opportunities to play in attack, given he will not ask Benzema, Ronaldo and Gareth Bale to start every week.
"I’m sure the three strikers can’t play all the games," he said. "That would be impossible."
Rodriguez's inclusion effectively resulted in Xabi Alonso dropping out, with Toni Kroos and Luka Modric having been selected in midfield.
Ancelotti insisted, though, that it would be a mistake to read too much into the ex-Liverpool man's exclusion.
"Xabi Alonso had played two games in a row and I wanted to give him a rest," he said. "It’s hard to perform well every three days."
Madrid's next Primera Division outing comes Sunday, when Ancelotti's men travel to San Sebastian to take on Real Sociedad.