 On 31 August 2019, he scored his first professional goal in a 2–2 away draw between Barcelona and Osasuna at the age of 16 years and 304 days, becoming the Barcelona senior team's youngest goalscorer ever and the third-youngest scorer in the history of La Liga.On 14 September 2019, in his first career start, Fati became the youngest player in the history of La Liga to score and assist in the same match, at the age of 16 years and 318 days.Fati scored in the 2nd minute and assisted Frenkie de Jong's goal in the 7th minute of an eventual 5–2 home win against Valencia.