Neymar was carried off the Parc des Princes pitch in tears during PSG's 3-0 Classique victory over Marseille on Sunday after riding a challenge from Bouna Sarr before twisting his right ankle as he planted his foot on the turf.
On Monday, Neymar posted a photo of his foot in heavy strapping after being taken to hospital and, although head coach Unai Emery said in his post-match news conference that the injury is not serious, it remains to be seen whether the forward will be fit in time to face Madrid on March 6.
While the absence of Neymar would undoubtedly weaken PSG's star-studded attack, Zidane – whose Madrid side lead 3-1 from the first leg ahead of the return tie in Paris – expressed a desire for the Brazil star, who continues to be heavily linked with a move to the Santiago Bernabeu, to play.
"I'm not happy if Neymar is injured. Hopefully, he can play. I'm never going to want an opposing player to get injured.
"I do not think it influences next week's game. There will always be a player who plays if it's not him.
"I did not like it when he got injured, I was watching the game. I don't think everything revolves around Neymar, but I hope it's nothing serious."
Cristiano Ronaldo has found his form at a potentially vital part of the season, having struggled in front of goal in LaLiga before the turn of the year.
The Portugal star has 10 league goals in his last six appearances and Zidane suggested there is an element of deliberation about him finding form in the second half of the season, with the World Cup coming up.
"It is a bit of everything," Zidane said. "He knows his body very well. We talk often and it's important that he's at the top of his game, in the best shape possible.
Possession— Real Madrid C.F. (@realmadriden) February 26, 2018
Crossing and finishing
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"It's important he rests sometimes too. It's a long season and at the end of the season there's a World Cup.
"Sometimes players don't think about it and take it one day at a time, but at the back of their mind they know there's a World Cup around the corner. I've lived it. It happened to me."