Real eased into the quarter-final stage of Europe's elite club competition after a 2-1 victory against the Ligue 1 leaders at the Parc des Princes on Tuesday.
But club-record signing Gareth Bale, Luka Modric, Toni Kroos and fan-favourite Isco were all named as substitutes for the second-leg tie.
Lucas Vazquez, Marco Asensio and Mateo Kovacic were the surprise inclusions in the starting XI, but the less experienced members of the Los Blancos squad justified Zidane's tactical decision.
"It's the same as ever. I'm here to pick the players and prepare them for the match. We did what was expected. In the end it's the players who are convinced by what we're doing. That is the key: to believe in what we do," he said after the game, as quoted by AS.
"If they're [Kroos, Modric and Isco] on the bench I want to say they're at 100%. But I have to consider a lot of factors. The game could last for 90 minutes of more. I choose the 11 and later they can go on. We had a great game with other players.
"The team is the important thing. Bale didn't play in the first leg nor today, but that doesn't have anything to do with it. He's very important and will be right to the end."