Diego Costa's second-half header was enough to grab the points and take advantage after Barca were earlier held to a 1-1 draw at Valencia.
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.
The Argentinian has now scored in 12 consecutive La Liga games, but instead of his goal heralding the start of a Barca comeback, the Catalans were instead indebted to a couple of world-class late saves from Victor Valdes.
Barca still retain a nine-point gap over Atletico, with Real Madrid a further seven points back following their shock 1-0 reverse at relegation-threatened Granada last night.
Malaga's Champions League push suffered a blow as they were held to a 1-1 home draw 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.
Zaragoza's afternoon was soured slightly by the last-minute dismissal of Jose Mari for a second yellow card.
Mallorca's bid to revive their flagging fortunes after the January transfer window were immediately undermined by a 3-0 loss at Real Sociedad.
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.
Sevilla's resurgence under Unai Emery continued as they won for their fourth consecutive home game, 2-1 over Rayo Vallecano.
Ivan Rakitic and Alvaro Negredo got the goals either side of Alejandro Dominguez's 52nd-minute penalty.
The gap between Real Madrid and Barcelona can grow to 18 points after the capital club fell to yet another defeat against Granada on Saturday night.
New Granada boss Lucas Alcaraz enjoyed a dream first game in charge as his side pulled off a shock victory over Madrid at the Estadio Nuevo Los Carmenes. Should Barcelona win at Valencia later on Sunday, the Blaugrana would get to increase the gap to an impressive 18-point margin.
Alcaraz has only recently taken over the reins following the sacking of Juan Antonio Anquela, who left with the club in 17th place in the standings, two points above the relegation zone.
Osasuna's win over Celta Vigo earlier on Saturday also meant Granada had dropped into the bottom three by kick-off, but they climbed out again thanks to an own goal from Cristiano Ronaldo, who glanced a corner into his own net midway through the first half.
Emiliano Armenteros' second-half strike was enough to move Osasuna out of the relegation zone as they leapfrogged Celta Vigo with a 1-0 win at the Reyno de Navarra.
The hosts controlled a first period that was disturbed by a fierce wind in Pamplona and could easily have been in front before the break as Armenteros saw a header come back off the crossbar and Alvaro Cejudo was twice denied by good saves from Javi Varas.
However, the goal did arrive just 10 minutes after the break as Lolo cushioned a header into the Argentine's path and he rifled the ball low past Varas.
Getafe registered their first win in 10 games as they came from a goal and a man down inside 11 minutes to beat Deportivo la Coruna 3-1.
Miguel Angel Moya was sent off for bringing down Riki inside the area early on and Pizzi converted the resulting penalty to give the visitors the perfect start.
However, the hosts were level at the break as Diego Castro also scored from the spot after Ze Castro had upended Abdel Barrada, and when Depor's Abel Aguilar was sent off for a second bookable offence with 20 minutes to go, Luis Garcia's men took full advantage with two goals in two minutes from Alvaro Vasquez and Adrian Colunga.
Espanyol continued their climb away from the relegation zone with a deserved 3-2 home win over Levante.
Two goals in as many second-half minutes from Christian Stuani and Sergio Garcia effectively secured a win that was made to look more nervy after a late Obafemi Martins strike.
Espanyol dominated the opening period but relied on Vicente Iborra's own goal to hold a 1-0 half-time lead they relinquished almost immediately after the break to Ruben's clever header.
The hosts have lost just once in nine games under new boss Javier Aguirre, and they showed why they are on the rise as Stuani and Sergio Garcia combined to score the quickfire double which proved decisive.
Meanwhile on Friday, Athletic Bilbao had to battle from two goals down as they salvaged a valuable point with a 2-2 draw against Valladolid.
Sunday's La Liga Fixtures
Saturday's La Liga Results
Friday's La Liga Result