The 25-year-old had a successful trial period with the club and impressed club owner John Comitis.
Fielies is no stranger to Comitis, having come through the Ajax Cape Town development system, where the City owner was formerly a director.
He only ever made a single appearance for Ajax though, as a substitute against Maritzburg United in the 2012/13 season. He spent the next four seasons at Milano, making almost 100 starts in that time.
Fielies will compete for a place in the side with with Tshepo Gumede, Robyn Johannes and new Mozambican signing Jeitoso.
The Citizens also announced the signing of right wing back Craig Martin from Kensington.
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