Talks about a renewal are on hold and the 24-year-old has stressed his desire to play more regularly, but he made the most of his 14th LaLiga start of 2016-17 in Sunday's 3-0 home win over Alaves.
Isco scored Madrid's second goal with a powerful finish five minutes from time – his fifth strike in his last six league starts – and had a season-high 101 touches in an influential performance.
Zidane was asked if he wants Isco to sign a new deal after the match and he gave a positive response, as well as insisting the player himself wants to stay.
"Of course I want him to renew because he is a Real Madrid player and an important player for our team," said Zidane.
"The only thing he wants is to be here and play here. I'm delighted for the game he had.
"He did well playing between lines, he made the rest of the team play, he put in a very complete performance."
Zidane felt Isco's goal highlighted the quality that exists within Madrid's squad, but would not be drawn on whether he has promised the playmaker more game time next season.
"At the time of the second goal we had difficulties and had been losing possession, but then the ball arrived at Cristiano [Ronaldo], he passed to Isco and we scored," said Zidane.
"We know that at any moment we can do damage to our opponent – that is what this team has.
"What you need to be aware of is that every three days we have an important game. After that, everyone can think what they like.
"To be able to win the Liga or the Champions League, every single player in the squad is important. The players know that and that is why when Isco plays, he plays well.
"But there are 24 of us in this squad and everyone is important."