Forward Robert Lewandowski converted a first-half penalty to hand Barcelona a gritty 1-0 home victory over Rayo Vallecano on Monday, lifting them to first in the LaLiga table.
Barca capitalized on Real Madrid and Atletico Madrid slipping up over the weekend to jump from third place to the summit of the rankings. Barca are tied on 51 points with Real but lead on goal difference.
Atletico follow closely by a point, while Rayo Vallecano sit sixth with 35 points.
Lewandowski bagged the decider with a composed strike from the spot in the 28th minute after Pathe Ciss brought down Inigo Martinez inside the area.
Although Barca controlled possession, Rayo appeared the more threatening side and should have grabbed the equalizer when Jorge de Frutos squandered a header from close range in stoppage time.