The 31-year-old has returned to his native Venezuela, where he has signed for Carabobo FC as a free agent, six months after parting ways with Amakhosi. Castillo spent two seasons at Chiefs, though his final campaign was disrupted by injury.
His exit came as a surprise, leaving the Soweto giants with Sibongiseni Mthethwa and Thabo Cele as their primary central midfield options. During his spell at the club, Castillo made 41 appearances across all competitions, scoring five goals and registering two assists.
Despite playing club football in South Africa, Castillo continued to represent Venezuela, although he was omitted from several national team camps.
"I'm happy to be back in Venezuela. From abroad, I watched almost all the matches in the Betway Premiership and it's a very even competition. That's good for a player's growth," Castillo was quoted by FarPost.
"The South African league is very competitive and physically demanding. It helped my game because I'm a player who pushes himself to the limit, and performing at that level allowed me to reach my best physical condition."
Castillo believes he is now entering a more mature phase of his career and is eager to make an impact at his new club.
"I feel I'm at a stage where I have more experience and can contribute a lot to Carabobo," he added. "I'm a dynamic player who can help both defensively and offensively. I'm a defensive midfielder, but I also like to score goals."
The Venezuelan international feels Carabobo's style of play suits him perfectly.
"I'm joining a team that's ideal for my style because they like to dominate possession and create space to attack. That will help me create more scoring opportunities. I'm coming with a strong desire to return to the national team. Carabobo have been playing good football, and I'm confident they'll help me get back to top form," he concluded.