On 9 March 2018, Carlos Isaac renewed his contract until 2020.[4] His La Liga debut came the following 1 April, as he started in a 1–0 home win against Deportivo de La Coruña.[5]
On 4 August 2022, Carlos Isaac signed a three-year contract with F.C. Vizela of the Portuguese Primeira Liga.[8] The following 17 January, however, he returned to Alba and signed a permanent two-and-a-half-year contract with the club.[9]
On 31 July 2024, Carlos Isaac terminated his link with Albacete[10] and signed a one-year deal with fellow second division side Córdoba CF the following day.[11]
^"Carlos Isaac, un campeón agradecido" [Carlos Isaac, a thankful champion] (in Spanish). El Periódico de Extremadura. 13 April 2016. Retrieved 2 April 2018.