Real Madrid were held to a third consecutive LaLiga draw in a 1-1 tie at Girona on Sunday, allowing Barcelona to retain pole position.
Azzedine Ounahi fired the hosts into a surprise lead before halftime, with Kylian Mbappe earning Madrid a point from the penalty spot.
After Barcelona beat Alaves on Saturday to move top of the table, Madrid needed a victory at Girona to reclaim top spot but now sit second, a point behind the champions.
The draw increases the pressure on Madrid coach Xabi Alonso, after recent rumours suggesting his future is insecure in the Madrid dugout.
"We are up there, it's all very even, it's a long season and we have to continue," Alonso told reporters.
"I liked the reaction from the players. It was not enough to turn it around but we were close, and we have to continue with the unity we have, being self-critical enough, and wanting to win away from home, with this phase of the calendar where we have so many matches (away)."
Madrid travel to face Athletic Bilbao on Wednesday for a fourth consecutive league match on the road, a game moved because of the club's participation in the Spanish Super Cup in January.
"The table will be hard-fought, there will be lots of movement. We're playing for three points but it would be a good moment to win, in Bilbao," added Alonso.
The Spanish coach brought centre-backs Eder Militao and Antonio Rudiger back after injury and maintained Brazilian forward Vinicius Junior in attack alongside Kylian Mbappe, who scored four at Olympiacos in the Champions League in midweek.
Mbappe and Arda Guler fired off target for Madrid early on in a hotly-contested but scrappy clash, in front of a raucous home crowd.
A poor Trent Alexander-Arnold pass allowed Girona forward Vladyslav Vanat in but his pass was intercepted when he might have opted to shoot.
SHOCK LEAD
Girona goalkeeper Paulo Gazzaniga made a fine save to keep out Eder Militao's header before Mbappe thought he had fired Madrid ahead.
However, the French superstar's goal, flicked home from close range, was disallowed as the ball bounced off his hand before he scored.
Just moments later, Morocco international Ounahi fired Girona ahead, rifling home from just inside the area to stun their illustrious visitors.
Catalan minnows Girona, 18th, have twice beaten Real Madrid at Montilivi since making their top flight debut in 2017 and for a while it looked like they were going to manage it again.
Real Madrid goalkeeper Thibaut Courtois made a stunning save to tip away Vanat's drive across goal before Los Blancos fought back.
After having a goal disallowed for offside Vinicius was clumsily felled in the box by Hugo Rincon.
Mbappe smashed the resulting penalty into the bottom left corner past Gazzaniga's dive for his 14th LaLiga goal of the campaign.
Vinicius curled narrowly over and Mbappe whipped a shot inches wide in stoppage time as Madrid could not find a winner.
"The truth is we wanted three points, you could see the team trying to get them," Girona's Gazzaniga told Movistar.
"We had more chances, but thinking about it calmly, a point against an opponent like this is good. Right now though, we're a bit annoyed as we could have taken three."