Messi, Valdes rescue point
Barcelona were indebted to goalkeeper Victor Valdes for producing two super saves to secure a 1-1 draw from a tough assignment against Valencia at the Mestalla.
Barca had the opportunity to establish an 18-point gap over arch-rivals Real Madrid following the capital club's shock loss at Granada, but turned in a performance well below their usual high standards as Valencia were unfortunate not to take the win.
Ever Banega opened the scoring with the first shot of the match after 33 minutes, but Valencia's lead lasted just five minutes as Lionel Messi fired home from the penalty spot after Pedro had gone to ground in the area under the challenge of Joao Pereira.
Valencia came closest to winning the match in the second half but Valdes produced two saves out of the top drawer to first deny Sergio Canales and then the dangerous Roberto Soldado.
Atletico Madrid cut the gap to Barca to nine points as Diego Costa's second-half header was enough to hand them a 1-0 win against disappointing Real Betis.
Arda Turan had a hat-trick of early chances but failed to find the net as Atleti started brightly, but the game descended into a scrappy affair with both defences on top until Betis goalkeeper Adrian flapped at a corner just after the hour mark and Costa was on hand to nod home his 11th goal of the season.
Atleti's 20th successive home victory maintained their 100% record at the Calderon this season, while a second straight defeat for Betis leaves them in fifth.
Malaga's Champions League push suffered a blow as they were held at home 1-1 by lowly Real Zaragoza.
The hosts fell behind to an early Helder Postiga strike and although Alarcon Isco levelled from the penalty spot 10 minutes later, Malaga were far from their best with Zaragoza enjoying the majority of the game's chances.
However, some of Zaragoza's joy at claiming a tough point away from home was dampened by the last-minute dismissal of Jose Mari for a second bookable offence.
Sevilla's resurgence under Unai Emery continued as they won for their fourth consecutive home game, 2-1 against Rayo Vallecano thanks to goals from Ivan Rakitic and Alvaro Negredo.
Negredo missed a host of chances as Sevilla dominated the first period, but they were eventually gifted a half-time lead moments before the break. Ruben Martinez rushed from his goal to clear but only succeeded in presenting the ball to Rakitic who chipped delicately into an empty net from 40 yards.
Rayo were level though six minutes into the second half as Fernando Navarro pulled down Alejandro Dominguez as he tried to connect with Roberto Trashorras' corner and Dominguez himself stepped up to send the ball low past Beto.
However, Sevilla were back in front just three minutes later as wonderful play from Jesus Navas and Coke set up Negredo to backheel the ball in from close range for his third goal in as many games over the past six days.
Sevilla held on despite having Rakitic sent-off for a second bookable offence in stoppage time.
Real Mallorca's bid to revive their flagging fortunes after the January transfer window were immediately undermined by a second-half onslaught at Real Sociedad as they were beaten 3-0.
The Islanders called new names Fernando Tissone and Alan Hutton into their starting XI, while Antonio Lopez returned on the bench, but they failed to provide any inspiration as Mallorca instead lost ground in their survival fight.
Javi Marquez's dismissal on the half-hour, following two cautions in the space of four minutes, paved the way for Sociedad to surge to victory after half-time with goals from Gonzalo Castro, Carlos Vela and Diego Irfan.
Mallorca have now won just once in 17 league games and are four points adrift of safety. Sociedad are entrenched in the top half of the table following a seven-game unbeaten run at home.