Cristiano Ronaldo was rested and the supporting cast failed to show up as Real Madrid endured a shock 1-0 defeat away to Espanyol in La Liga on Tuesday.
Gerard Moreno struck in the 94th minute at the RCDE Stadium as Real's rotated line-up felt the full punishment for a slack and disjointed display. Gareth Bale, Marco Asensio and Isco all struggled, the trio squandering the chance to impress ahead of next week's Champions League second leg with Paris Saint-Germain.
Bale was certainly not the only Real player out of sorts but the 28-year-old, now back to full fitness, was perhaps under most pressure to stake his claim.
After missing with a number of efforts at goal, and receiving a yellow card in the first half, he was finally replaced with nine minutes remaining.
Zidane, however, would not be drawn on the performance either of Bale or the rest of his stand-ins after the match.
"If you lose here today it is because things did not work for many reasons, not just because of a player or a play," he told beIN Sports.
Instead, it was Gerard who stole the show as Espanyol scored a deserved win that sees them climb to 13th in La Liga. Real, meanwhile, will fall 17 points behind leaders Barcelona if the Catalans overcome Las Palmas on Thursday.
"If the result is not what we want then it is a step back," Zidane said. "I do not have to reproach my players, we played the game but we did not get what we expected."
With PSG left praying for a miracle after Neymar was stretchered off with a foot injury on Sunday, Zidane wrapped his own star player up in cotton wool, as Ronaldo was not even included on the bench.
Zidane would not be drawn on Neymar's chances of recovery.
"We have to wait, all we know is he is injured," the Frenchman said.
Bale left frustrated
Karim Benzema was also rested, allowing Bale his 116th La Liga appearance, drawing him equal with David Beckham.
The Welshman almost gave the visitors an early lead, reacting first to Achraf Hakimi's deflected cross but poking his near-post header too close to Diego Lopez.
Real, however, gradually ceded the ascendancy to Espanyol, who twice could have been in front were it not for a combination of sloppy finishing and bad luck.
Gerard was the protagonist in both, the forward first failing to capitalise on a skewed Raphael Varane clearance and then doing brilliantly to control a thundering half-volley from Carlos Sanchez, only to see his finish ruled out for offside.
Replays suggested Real had been fortunate to escape. Bale wanted a penalty when his driven shot was blocked by the hand of Victor Sanchez at the back post but the defender knew little about it.
Instead, Espanyol sustained their momentum at the start of the second half, with Keylor Navas able only to watch as Sergi Darder's header plopped onto the top of the crossbar.
Bale cut a figure of increasing frustration. One ballooned shot over from the edge of the area was quickly followed by two scuffed finishes. They were not easy chances but a player of his calibre would have hoped to do better.
With just over 20 minutes left, Benzema replaced the ineffective Isco but Espanyol came closest to snatching a winner when Gerard's header was saved from six yards.
Bale trudged off in the 81st minute and Gerard finally got the goal he deserved, catching Sergio Garcia's cross perfectly with a brilliant shot that sailed past Navas and into the corner.