Real Madrid’s La Liga title bid recorded a setback on Sunday after they were held to a 2-2 draw at home to Celta Vigo.
They were denied all three points by a late strike from Santi Mina.
Mina latched on to a classy through ball from former FC Barcelona midfielder Denis Suarez and produced a clinical low finish to equalise in the 85th minute.
The draw trimmed Real Madrid’s lead over FC Barcelona to one point.
Celta Vigo took an early lead through Russian striker Fedor Smolov and Real Madrid struggled to respond.
This led to the home fans booing their players off the pitch when the half-time whistle was blown.
But the league leaders came out stronger after the break and Toni Kroos levelled in the 52nd minute, shortly after team captain Sergio Ramos had a goal ruled out for offside.
Ramos then scored from the penalty spot to put Zidane’s side in front in the 65th minute after Eden Hazard was tripped by Celta Vigo goalkeeper Ruben Blanco
Hazard was making his first outing in almost three months after recovering from an ankle injury.
“Dropping two points at home hurts me a lot,” Zidane told reporters.
“Celta Vigo are a good team that don’t deserve to be near the bottom of the league, but it’s painful to lose the two points after we made such a big effort.”
Real Madrid forward Gareth Bale meanwhile avoided a possible red card for a wild tackle on Celta Vigo’s Rafinha, escaping with only a booking.
The draw ended a five-game winning streak in the league for the leaders and left them on 53 points after 24 games.
They are one point ahead of second-placed FC Barcelona who beat Getafe 2-1 at home on Saturday.
Celta Vigo, who had lost on their last seven league visits to the Santiago Bernabeu, climbed out of the relegation zone into 17th place in the standings.
“I’m happy with my performance. Not so happy with the draw, but I think we can do better in our next game,” said Hazard.
“When you are winning 2-1 you should win the game. They are good players but they came here just to defend. They had only two chances and scored two goals.”