With the win, Madrid are once again four points up in the LaLiga Santander table over second-place Barcelona and closing in on their first league title since 2016/17.
Zidane's focus stayed on the side's defensive efforts as he made clear how happy he is with their work.
"Not conceding goals is impossible," he began, "but it's true that we're conceding very few.
"We have to keep doing what we're doing and we have a very fit Courtois.
"The team don't concede a lot."
Real Madrid's last three wins have been aided by penalties being awarded, but the Frenchman doesn't read too much into it.
"If there's a penalty then there's a penalty," he said.
"It was a good move. That's it.
"The important thing is that we score goals."
The title is now within touching distance with just five points needed to clinch it and it could be wrapped up as early as Monday evening.
"We're trying," Zidane continued.
"There are still three games to go and we don't know what will happen.
"Now it's time to rest because there's not a lot of time, although it is better to rest after a win."