Born in Sabadell, Barcelona, Catalonia, Isaías was a CF Badalona youth graduate, and started playing professionally with that club in the Segunda División B while also working as a part-time plumber.

[10] He repeated the feat in the 2016 A-League Grand Final in an eventual 3–1 defeat of Western Sydney Wanderers FC, through a 34th-minute free kick.

[11] On 23 September 2017, Isaías was announced as captain at Adelaide United's season launch, taking over from Eugene Galekovic who transferred to Melbourne City FC.

[19] At the end of the 2023–24 campaign, Isaías agreed to a new contract alongside his teammate Javi López, one that would see out his playing career as he also completed a coaching badge with the club.

[24][25][26] Isaías was described by Adelaide manager Josep Gombau as his "foot soldier", being a complete footballer with technique, speed and controlled aggression.