With two goals in less than 10 minutes, Lamine Yamal led Barcelona to its fifth straight victory at the start of the Spanish league season.
The teenager's double, plus second-half goals from Dani Olmo and Pedri, gave Barcelona a commanding 4-1 win at Catalan rival Girona on Sunday, keeping a four-point lead at the top.
Atletico Madrid kept pace by beating last-place Valencia 3-0 with goals from Antoine Griezmann and newly signed players Julián Álvarez and Conor Gallagher, while Real Madrid had won 2-0 at Real Sociedad on Saturday with goals from Kylian Mbappé and Vinícius Júnior.
Along with Atletico and Madrid, Villarreal was the other team four points behind Barcelona after winning 2-1 at Mallorca on Saturday.
“To help the team it's important to score the goals and to do whatever is needed,” Yamal said. “The first match after the international break is always complicated. Now we can start focusing on the match against Monaco (in the Champions League on Thursday).”
Yamal's goals on Sunday were his second and third of the season. The 17-year-old Spain international opened the scoring after stealing the ball from a defender and sending a close-range shot into the net in the 30th minute. He scored again in the 37th after picking up a loose ball inside the area.
Olmo's third goal since joining Barcelona this season came from a tight angle in the 47th, and Pedri sealed the easy victory with a goal from inside the area in the 64th.
Olmo, who had to be replaced in the second half because of a right leg injury, became the first player to score in his first three league games for Barcelona since Cesc Fabregas in 2011. Only Zlatan Ibrahimovic, in 2009, achieved the same feat this century.
Cristhian Stuani scored Girona's lone goal in the 80th.
The hosts were initially awarded a penalty kick for a handball inside the area just before halftime, with Barcelona leading 2-0, but the call was reversed by video review.
Barcelona played with 10 men from the 87th after Ferran Torres was sent off for a hard foul on an opponent.
Poland striker Robert Lewandowski played his 100th match with Barcelona.
Girona, a surprise third-place finisher last season, won both league games against Barcelona last season.
Atletico Madrid tops Valencia
Newly signed Argentina forward Álvarez and England midfielder Gallagher scored their first goals for Atletico Madrid in the team's 3-0 win over last-place Valencia.
Álvarez sealed the home victory in stoppage time after Gallagher had opened the scoring in the 39th and Griezmann had doubled the lead in the 54th.
“I didn't feel like I was under pressure to score,” Álvarez said. “I was ready for when the opportunity appeared.”
It was the second consecutive win for Atletico, and third in five league matches. Diego Simeone's team drew its other two games.
Valencia has opened its season with four losses and a draw — 1-1 against Villarreal in the previous round.
Earlier Sunday, 10-man Athletic Bilbao won 3-2 at Las Palmas, which hasn't won in 19 straight league games going back to last season. It was the second win for Athletic this season.
Celta Vigo beat Valladolid 3-1 at home for its first win after two consecutive losses. It was the fourth straight game without a win for Valladolid after it opened with a victory at Espanyol.
