The teenage sensation looked poised to make a first-team breakthrough at the Brazilian giants this season after starring with the academy ranks but the coronavirus crisis prevented his progression with the league suspended.
Barcelona confirmed he will move straight into the club's reserve team upon arrival as they continue their pursuit of securing the most highly-rated prospects around the world.
"Gustavo Maia is 19 years old and joined Sao Paulo at the age of 14," read the statement on the club's website as the deal was confirmed on Thursday.
"After three trials with the club, he was brought into their academy, and since then has scored goals and won 7 trophies at all levels. His best season in front of goal was in 2018, when he scored 30 times in 36 games."
The Spanish giants have already signed Spain wonderkid Pedri, Brazil midfielder Matheus Fernandes, Trincão and Miralem Pjanic ahead of next season.
