Yes, as transit without visa arrangements are only valid for transits of less than 8 hours. According to the Department's web site (emphasis added):
If you are from an eligible country (see eligible countries listed below) you can transit through Australia on your way to a third country without an Australian visa provided you meet all of the following criteria:
- will arrive in Australia by aircraft
- have a confirmed ticket to leave Australia to travel to a third country by aircraft within 8 hours of arriving
- have valid travel documents to enter that country
- must not need to clear immigration or leave the airport transit lounge for any reason before boarding your onwards flight.
Even if you meet all other criteria, including being of an eligible country, if you need to clear immigration, for example to collect or transfer baggage onto, and/or to board, your onwards flight, you will need an Australian visa to do this. For more information see Transit facilities at Australian airports.
As a South African citizen, you will need to apply for a Transit (subclass 771) visa. Alternatively, if you can reschedule your flight so that you will be transiting Australia for less than 8 hours, you will be able to utilise the transit without visa arrangements.