The young Guinean's brace at 17 years and 96 days broke the record of former malaguista Juanmi. Juanmi got it in Zaragoza with 17 years in 115 days.
Fati has been setting records since featuring for the Catalan club, becoming the second youngest player to play a league game in a Barcelona shirt.
Ansu already has five official goals this year with Barça, four in the League and one in the Champions League.
Fati became the youngest player in the history of Barça to score an official goal in LaLiga after finding the net against Osasuna .
Ansu also became, thanks to his goal against Inter in the Champions League, the youngest scorer in the history of the competition.
He did it with 17 years and 40 days and beat Peter Ofori-Quaye, who was 17 years old and 195 days old when he scored Rosenborg with Olympiacos.