Castro signed a two-year contract extension with Chiefs as his initial contract with the club was set to expire at the end of June.
The striker joined Chiefs from Sundowns in 2018 scoring 20 times for the Soweto giants.
"This is sensitive for me because I have not won a trophy yet with the team. And to leave without a gold medal would be a defeat for me," Castro was quoted by the Chiefs website.
"I wish to win something. And I think with the squad we have at the moment; we are capable of doing well. My family is excited about this development. We are happy to remain in South Africa. Thank you once more to the Chairman and the Club," he concludes.
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