Barcelona suffered a major setback to their hopes of retaining their La Liga title when they were held to a 1-1 draw by city rivals Espanyol on Sunday, a result which left them five points behind Real Madrid.
Barcelona took a 16th-minute lead through a header from Cesc Fabregas - the club's 100th goal in all competitions this season - but were rocked when Alvaro Vazquez scored an 86th-minute equaliser with a low header.
Gerard Pique hit the woodwork in injury-time as Barca's last chance for the three points went begging, leaving Real Madrid, who had coasted to a 5-1 win over Granada on Saturday, in control of their title destiny.
"Difficult game tonight, we left two points but we have to keep going till the end. Now time to rest," Fabregas wrote on his Twitter account.
Espanyol have an exciting young side and coach Mauricio Pochettino promised that they would go out to attack which they did.
Joan Verdu was denied twice inside the opening minutes - first by keeper Victor Valdes and then Pique, who cleared the follow up off the line.
At the other end, Espanyol keeper Cristian Alvarez played a ball straight to Lionel Messi in front of goal but fortunately for the shot-stopper the Argentine handled it and was yellow-carded.
Barca did take the lead when Fabregas, left unmarked, headed home inside the penalty area after 16 minutes and again the keeper was slow to react as the ball went underneath his dive.
Espanyol had chances from distance, notably from Sergio Garcia, while Thievy Bifouma also looked dangerous.
It was far from a vintage performance from Barcelona but they looked in control and they could have had a second from Messi who clipped the post with 12 minutes to go.
But then Espanyol stunned the champions when Thievy headed on a cross to Vazquez who powered it home in front of goal with a diving header.
Pique crashed a shot against the woodwork in stoppage time but Espanyol hung on for a point.
Barcelona's coach Pep Guardiola stressed after the game that the season still had a long way to run.
"The league has a long way to go and there are still many points left." to be won and lost, he said.
"I was happy with much of the second half, though we lacked presence in the penalty box."
Real had coasted to a 5-1 win over Granada on Saturday, the minnows first visit to the Bernabeu in 36 years.
They went in 2-1 at the break with goals from Karim Benzema and Sergio Ramos while Mikel Rico scored in between for Getafe.
The game turned straight after the restart with strikes from Gonzalo Higuain and another for Benzema before Cristiano Ronaldo, with his 21st of the league season, wrapped up the scoring a minute from the end.
"The third goal after the break was the key," said Real assistant coach Aitor Karanka.
"We knew that Granada were going to be a difficult opponent as they showed in the first half but they are a team which is built to defend and so after we had scored the third - and with all the space at the Bernabeu - they had more problems."
New Villarreal coach Jose Francisco Molina was denied a perfect start in his new job as a late goal from Aritz Aduriz saw Valencia earn a 2-2 draw after having been two goals down on Sunday.
It was a baptism of fire for Molina who replaced Juan Carlos Garrido, dismissed before Christmas after a woeful start to the campaign, as they faced local rivals Valencia who were looking to reinforce their Champions League claims.
Marco Ruben put Villarreal ahead after 14 minutes with a clinical finish.
Valencia had no time to respond when they went further behind as Gonzalo Rodriguez headed home a Borja Valero free-kick.
Sofiane Feghouli reduced the arrears before the break while Roberto Soldado and Feghouli both fired wide at the start of the second half.
Villarreal appeared to be heading for their first win in nine attempts until sloppy defending from Florian Lejeune allowed in Aduriz to fire an equaliser.
"I am happy because we worked hard and played well in stages. I think that we deserved to win but that wasn't what happened and that is that. We have to be satisfied with our football and the fact that we should be higher up the table," said Molina.
Elsewhere, there was no movement among the European places with goals at a premium as Levante drew 0-0 with Mallorca on Saturday and there were also no goals for Osasuna and Malaga who drew 0-0 against Real Sociedad and Atletico Madrid respectively.