Lamine Yamal's quickfire double in under 10 minutes powered Barcelona to their fifth consecutive win in La Liga, securing a dominant 4-1 victory over Catalan rivals Girona on Sunday.
Second-half strikes from Dani Olmo and Pedri sealed the win, keeping Barcelona four points clear at the top.
Meanwhile, Atletico Madrid stayed close behind with a 3-0 triumph over bottom-placed Valencia, thanks to goals from Antoine Griezmann and newcomers Julian Alvarez and Conor Gallagher.
Real Madrid had already secured a 2-0 victory over Real Sociedad on Saturday, with Kylian Mbappe and Vinicius Junior finding the back of the net.
Along with Atletico and Madrid, Villarreal were 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 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 minute, 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 due to a right leg injury, became the first player to score in his first three league games for Barcelona since Cesc Fàbregas in 2011. Only Zlatan Ibrahimović, in 2009, achieved the same feat this century.
Cristhian Stuani scored Girona's lone goal in the 80th minute.
The hosts were initially awarded a penalty 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 minute after Ferran Torres was sent off for a hard foul on an opponent.
Poland striker Robert Lewandowski played his 100th match for Barcelona.
Girona, a surprise third-place finisher last season, won both league games against Barcelona last season.
Newly signed Argentina forward Alvarez 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 minute and Griezmann had doubled the lead in the 54th.
“I didn’t feel like I was under pressure to score,” Alvarez said. “I was ready for when the opportunity appeared.”
It was the second consecutive win for Atletico and their third in five league matches. Diego Simeone’s team drew their other two games.
Valencia have opened their 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, who haven’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 their first win after two consecutive losses. It was the fourth straight game without a win for Valladolid after they opened with a victory at Espanyol. Valladolid lost three of their next four games.
