Injuries to Lionel Messi and Barcelona's other top attacking players gave an unknown 16-year-old teenager from Guinea-Bissau the rarest of chances to bring a stunned Camp Nou crowd to its feet.
Ansu Fati became the youngest player to score in Barcelona's stadium on Saturday when he made his first start for the defending champion, which was without Messi for a fourth game this season.
After his second-minute opener he also set up a quick second goal to further impress and put the hosts on their way to a 5-2 rout of Valencia.
Luis Suarez, who hadn't played in a month due to injury, netted Barcelona's fourth and fifth goals after replacing Fati with half an hour remaining.
Fati received a huge round of applause when he left and the fans chanted his name.
Fati, officially a player on its third team for 16-18 year olds, made his first appearance for Barcelona's main squad three rounds before. He established a milestone in his second match as the youngest player to score in la Liga in the club's history at the age of 16 years, 304 days in a 2-2 draw at Osasuna.
Fati needed only two minutes on Saturday to write his name into the club's history a second time.
With his second touch of the ball, he rifled in a pass from Frenkie de Jong who found him arriving to the center of the area after a dummy run by Antoine Griezmann.
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