Arnaldo Castillo

Nine on his back at O'Higgins. Arnaldo Castillo arrived in Rancagua in December 2022.

The route to that point ran through most of the Chilean second tier. Castillo turned professional with Universidad de Concepción in 2016 and was then sent out on loan three years running — 13 matches and five goals at Naval in 2017, 22 and nine at Arturo Fernández Vial in 2018, 22 and nine at Iberia in 2019. Iberia signed him outright the following year, and he returned 12 goals in 20 appearances across 2020 and 2021 before moving to Deportes Puerto Montt in March 2021. That was his heaviest workload: 32 matches, 10 goals.

He went back to Universidad de Concepción in January 2022 and had the best season of his career, finishing as the club's leading scorer with 11 goals in 25 matches as they won promotion to the Chilean top flight. O'Higgins came for him at the end of that year.

Since then he has played 96 league matches for the club, scoring 18, with six more goals in 11 Copa Chile ties and three in eight Copa de la Liga games. Twelve continental appearances, in the Copa Libertadores and Copa Sudamericana, have brought three goals.

Castillo holds both Paraguayan and Chilean citizenship, and in March 2026 the Paraguayan federation approached him. He appeared on preliminary lists for both countries. Neither made him a final squad, and he is yet to play a senior international.