Since then, the 28-year-old has proved to be a consistent performer, and recently he won the club's March player of the month ahead of Aishi Manula and Mozambique international Luis Miquissone.
The Mnyama communications officer has now taken to his social media platforms to hit back at those who criticized the signing.
"Where are those who said Simba have old defenders who will struggle this season?"
"Even some analysts were quick to claim the [Onyango] signing will flop. How are you feeling now? Let us assume Oyango is old, so which youthful defender can be compared to him?
"Lest you don't know, Onyango is used to winning awards and many more are coming. Critics don't have a place to hide their faces."