Robert Lewandowski's 32-minute hat-trick was the fourth quickest by a Barcelona player in La Liga
Robert Lewandowski scored a first-half hat-trick as Barcelona re-established their three-point advantage at the top of La Liga with a comfortable win at Alaves.
Real Madrid's home victory over Villarreal on Saturday evening had temporarily moved them level with Hansi Flick's side.
However, the visitors - who suffered a shock defeat by Osasuna last weekend - always looked in control after Lewandowski nodded them in front early on from Raphinha's curling delivery.
The 36-year-old's second, a close-range finish, came after more good work from the Brazilian.
And his and Barca's third came as he reversed a shot past home goalkeeper Antonio Sivera from Eric Garcia's pass.
The Poland forward has now scored 12 goals in 11 games in all competitions for Barca, who are averaging over three goals a game in the Spanish top flight this term.
"I had some good passes and they made it easier for me to score," Lewandowski said on DAZN.
"We played well from the first minute and we wanted to attack and score goals. We were more in control in the second half.
"We have a very good group. I think we can play better but we have improved all the things we lacked."
The hosts, who threatened sporadically, thought they had pulled a goal back on the stroke of half-time but Toni Martinez's goal was ruled out for an offside in the build-up.
