The Ballon d’Or winner was dismissed eight minutes from time after appearing to aim a kick and slap at Cordoba defender Edimar, and has subsequently apologised for the incident.
"I didn't see anything and haven't spoken with him," Ancelotti said. "I can't judge what happened."
The coach was quick to turn attention back to the game.
"Cordoba played very well," he continued.
"They fought for every ball and were very good on the break. We struggled in this game but the important thing was to take three points and we've done just that."
It was Ronaldo’s fourth Liga red card since his 2009 arrival in Madrid.
Gareth Bale rescued three points for the league leaders with a late penalty, and expressed Ronaldo’s regret for his 82nd-minute dismissal.
"There's still a long way to go this season, a lot of games before we talk about the title," Bale said.
"What's clear to us is that there can be games like this one when the going gets tough. Cristiano is really disappointed with his red card, but these are things that happen in football."
It was the first time Real Madrid have had to wait until the final five minutes of the season to earn points in the current campaign.
The victory leaves them one point clear of second-placed Barcelona with a game in hand.
