Born in Campo Grande, Mato Grosso do Sul, Locatelli joined Chapecoense's youth setup in 2015, aged 16.
[1] Promoted to the main squad for the 2019 campaign, he made his senior debut on 24 February of that year, coming on as a half-time substitute for Alan Ruschel in a 0–2 Campeonato Catarinense away loss against Marcílio Dias.
[2] Locatelli scored his first goal as a professional on 31 March 2019, netting his team's second in a 2–0 home win against Brusque.
[3] He made his Série A debut on 14 September by replacing Elicarlos in a 1–2 home loss against Vasco da Gama,[4] and scored his first goal in the category on 8 December in a 1–1 away draw against the same opponent.
[8] He was a regular starter in the club's 2021 Campeonato Paulista campaign, featuring in 13 matches.