Matsi committed to a four-year deal that will have him stay with the Mother City club until 2022.
The four-year deal comes after City chairman John Comitis said he would like to tie down key players to long-term contracts to help the team compete for silverware each season.
The 28-year-old is the third member of McCarthy’s squad to sign a long-term contract with the club.
Defenders Edmilson Dove and Taariq Fielies signed four- and five-year contracts, respectively.
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