Matsi has signed a new four-year contract at the Cape-based outfit, which will stretch until his 32nd birthday.
The former University of Pretoria midfielder is one of the club's founding members, having migrated to the Mother City when Mpumalanga Black Aces sold its franchise to John Comitis ahead of the 2016/17 season.
City have since rewarded the 28-year-old, making sure his loyalty remains with the club until 2022.
✍The club congratulates midfielder Mpho Matsi on signing a new four year contract extending to June 2022!— Cape Town City FC (@CapeTownCityFC) September 12, 2018
Mpho has formed an integral part of the City squad over the last 3 seasons, making 52 appearances for the club. #iamCityFC#Matsi2022 pic.twitter.com/1iUdlwEt2G
Matsi was a key figure in The Citizens' central midfield alongside Austrian enforcer Roland Putsche and Thabo Nodada last season, but missed a chunk of the campaign through a knee injury.
He has made four appearances this season, including two league starts and a sub appearance in their MTN8 semi-final second leg against Mamelodi Sundowns.