Mayambela was substituted before the half-time break after he was seen gesturing towards coach Eric Tinkler.
The midfielder then proceeded to walk straight down the tunnel, but he did return to the bench in the second half.
READ: Pule sends Pirates into Telkom last-eight
When asked about the incident following his side’s loss to Pirates, Tinkler said the club will be dealing with the matter internally.
Mayambela has since taken to social media to apologise for his actions.
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