Robert Lewandowski's first-half hat-trick guided LaLiga leaders Barcelona to a 3-0 win away at Deportivo Alaves on Sunday as the Polish striker extended his lead at the top of the league's scoring charts.

Lewandowski's treble made him the first player to net 10 goals in LaLiga this season and the second in Europe's top leagues after Manchester City's Erling Haaland.

The victory moved Barcelona to 24 points, three points clear of rivals Real Madrid, while Alaves are 12th with 10 points.

"There were some good passes and they made it easier for me to score. We played very well from the first minute, we wanted to attack and score goals," Lewandowski said.

"Scoring three goals in the first half puts you in more control in the second."

Barcelona dominated possession and skipper Raphinha had the ball in the net inside four minutes but the goal was ruled out for offside, a minute before the visitors lost Ferran Torres to an injury with Eric Garcia taking his place.

But Barcelona wasted no time in taking the lead when Lewandowski scored from a Raphinha free kick in the seventh minute, heading home an inch-perfect cross from the edge of the six-yard box.

Lewandowski has showed no signs of slowing down at 36 and he grabbed his second on a counter-attack when he checked his run to latch on to Raphinha's pass to score.

He completed his hat-trick in the 32nd minute when Garcia slipped a ball through to him and the Polish striker stretched to fire his shot past Antonio Sivera in the Alaves goal to net his 12th goal in 11 games in all competitions.

Alaves thought they had got on the board when Toni Martinez scored with a towering header towards the end of the first half but VAR ruled it out for offside.

"They were better than us in the first half but we had some chances, it was a pity about the offside," Alaves winger Abde Rebbach said.

"The team improved in the second half and we tried till the end."

The two goalkeepers were kept busy in the second half which saw some end-to-end action, with Barcelona's Inaki Pena ensuring they went home with a clean sheet while Sivera limited the damage for Alaves with six saves.

Barcelona's Lamine Yamal had a quiet game by his standards and he was taken off in the 67th minute. The 17-year-old winger, who has gone two games without a goal or assist, looked upset as he sat on the bench and threw his shin guard aside.

But as much as they tried, Barcelona could not get a fourth goal while fatigue also played a factor.

"The last five games, we've played every three days. I haven't played that many in my life," said Lewandowski, who played the full 90 minutes.

"We've had only a couple of days' rest between games and that makes a real difference. But we got what we wanted."