Teenage star Lamine Yamal struck twice as La Liga leaders Barcelona thrashed Girona 4-1.

Hansi Flick's side have now won all five of their opening matches and avenged two humiliating Catalan derby defeats by Girona last season with an emphatic victory at Montilivi.

Yamal's first-half double sent Barcelona on their way with Dani Olmo and Pedri Gonzalez adding further goals after the break.

Cristhian Stuani pulled one back for the hosts, last season's surprise package who finished third in only their fourth season in the top flight.

Girona lost several key players in the summer with coach Michel Sanchez forced to rebuild.

Barcelona have new momentum under former Bayern Munich and Germany coach Flick and produced their best performance of his reign to date.

"I think you can see the confidence we have, and when we have the ball, we have the quality to play and to create chances," Flick told reporters.

"I think today we had a lot of chances to score one or two goals more, but in the end I'm very happy with the performance of the team."