MADRID, Oct. 27 (Xinhua) -- FC Barcelona opened a six-point lead at the top of La Liga with a convincing 4-0 win away to Real Madrid in the first 'Clasico' of the season.
After a tightly contested first half, during which Kylian Mbappe was repeatedly caught in Barca's offside trap, Robert Lewandowski shifted the momentum decisively in Barca's favor with two goals in three minutes early in the second half.
Lewandowski opened the scoring with a confident finish past goalkeeper Andriy Lunin after a pass from Marc Casado, then added a second with a perfectly timed header at the far post from Alejandro Balde's cross.
Lamine Yamal added a third goal, and Raphinha sealed the 4-0 victory with a composed finish as Madrid left gaps in defense in the closing minutes.
Atletico Madrid's poor recent form continued as they lost 1-0 away to Real Betis, following Jose Gimenez's third-minute own goal as he tried to cut out Abde Ezzalzouli's cross from the left.
Ezzalzouli and Vitor Roque missed chances to extend Betis' lead against a lackluster Atletico in the first half, although Angel Correa hit the woodwork twice for the visitors in the closing minutes.
Ayoze Perez's late header secured a 2-1 victory for Villarreal in Valladolid, allowing them to move above Atletico into third place.
Thierno Barry headed Villarreal into the lead in the 28th minute, and the visitors could have wrapped up the match by halftime if not for fine saves from Valladolid's Karl Hein.
Mamadou Sylla equalized for Valladolid from the penalty spot, but Perez scored the winner six minutes from time.
First-half goals from Lucas Torro and Ante Budimir saw Osasuna win 2-0 away to Real Sociedad, lifting them to seventh ahead of Monday's game between Mallorca and Athletic Bilbao.
Osasuna coach Vicente Moreno was sent off in injury time for protesting a penalty awarded to Real Sociedad, which was subsequently overturned by VAR.
Three second-half goals from Diego Garcia, Darko Brasanac, and Sergio Gonzalez gave Leganes an important 3-0 win at home to Celta Vigo, lifting them out of the bottom three.
Garcia's goal broke the deadlock in a closely contested match, with Leganes taking advantage as Celta left space in defense while pushing for an equalizer.
Valencia remain bottom of La Liga after Mauro Arambarri's last-minute penalty earned Getafe a 1-1 draw against Ruben Baraja's team, who had taken the lead with Enzo Barrenechea's 36th-minute strike following a corner.
Rayo Vallecano beat Alaves 1-0 despite playing over 70 minutes with 10 men after Abdul Mumin was sent off.
Rayo Vallecano won when Gerard Gumbau's shot was tipped onto the bar by Alaves goalkeeper Antonio Sivera, only for it to bounce into the net off his back.
Alex Munoz's 41st-minute goal made it two wins in two games for Las Palmas since the arrival of Diego Martinez as head coach, as they won 1-0 at home to Girona.
Munoz finished at the far post as Las Palmas capitalized on Girona's injury woes.
Sevilla deepened Espanyol's crisis with a 2-0 road win, with winger Dodi Lukebakio scoring both of Sevilla's goals in the first half. ■