"There have been several inquiries but the main one which seems serious is from Zamalek. They had inquired before but at that time Chiefs were not willing to let him go. At the moment it seems he could leave for free as the club doesn't seem keen to extend his contract," the Siya source stated.
A second insider mentioned that Cele's arrival provides Chiefs the option to let Castillo explore new opportunities.
"It's his choice actually if Chiefs don't renew and if Zamalek are interested in him it will depend on the talks between the player and Zamalek. Of course there have been inquires and with Thabo Cele at the team now and the injury that Castillo suffered, this is his chance now," the second source stated.
Castillo joined Chiefs at the start of last season, playing the vast majority of games. This season, the 30-year-old's campaign was cut short due to his long-term injury, and it remains to be seen when he could return to action.
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Soccer Laduma contacted Chiefs for comment but did not receive a response by the time of publication.