- He excelled in the right wing position at Alianza Lima (where he was an idol) due to his great skill, power, speed, and explosive play. He is considered one of the best right wingers in the history of Peruvian football.
- Castillo was an idol in his right wing position, standing out for his speed, power, and great ability in the box. His story is that of a player who, through his talent, established himself as one of the best right wingers in the country.
- Castillo began his professional career in 1946 with Alianza Lima, where he quickly won the affection of the fans thanks to his explosive style and ability to create scoring opportunities. Coming from the "Los Bombones" youth academy in Chincha, he began to gain recognition in his homeland before making the leap to the capital. His agility and skill made him a key player for the team and a promising prospect for Peruvian football.
- His nickname, "Aretino," was given in honor of a famous racehorse from the 1950s, highlighting his speed and strength on the field. Castillo's ability to overcome defenses and assist or score goals earned him recognition from his contemporaries and the sports press, who recognized him as the most lethal right winger of his era. In addition to his individual achievements, he contributed significantly to Alianza Lima winning four Peruvian League titles in 1948, 1952, 1954, and 1955.
- This Peruvian, who arrived in the wake of a succession of players from that country during the Golden Age, played 72 matches and scored 24 goals.