After a 21st minute goal from Lehlohonolo Majoro, the Amakhosi looked to be heading towards victory until a 97th minute goal from Mandaza robbed the Soweto-based team of the victory.
Chiefs, though, only have themselves to blame after squandering numerous chances on goal throughout the match.
Chiefs were a bit slow out the blocks in the opening 45 minutes as they struggled to create any clear-cut openings.
That, however, was only until the 21st minute when George Lebese supplied a great through ball for Majoro to run onto and the Chiefs attacker made no mistake with a clinical finish from just inside the box, 1-0.
The Amakhosi continued to pile on the pressure thereafter with numerous corner-kicks and forays forward, but they were unable to find that final pass or cross that would lead to their second goal.
Majoro should really have doubled Chiefs lead two minutes into the second 45 when he found himself through on goal again, but this time he fired wide from about 14-yards out.
The Chiefs goal scorer was again in the thick of the action on the hour mark, but this time a fantastic save from Shu-Aib Walters denied him – the Maritzburg keeper showing great reflexes to stop a Majoro attempt from close range.
Walters was at his best again eight minutes later, this time flinging himself across the face of goal to tip a Bernard Parker shot around the post.
As the second half progressed Chiefs began to tire and United found their way into the game, but still the home side were unable to breach the Amakhosi defence, until the dying seconds of the match.
In the seventh minute of added time, Mandaza broke Chiefs hearts with a late headed goal – the Maritzburg man getting onto the end of a Peter Petersen cross to level matters, 1-1.
Maritzburg United: Walters; Cloete, Petersen, Booysen, De Jongh (Mandaza 34’), Awal, Buckley, Hendricks, Sarfo Gyanfi, Zulu, Malajila
Kaizer Chiefs: Khune; Moleko, Mothoho (Zvasiya 87’), Mashamaite, Ritchie, Letsholonyane, Katsande, Nale (Dladla 87’), Parker, Majoro