Chasing 270, South Africa appeared to lose their way after launching a blistering run chase in reply to Australia’s 269 in the third ODI, before Neil McKenzie (27), Morkel and Mark Boucher (31 not out) combined to take South Africa home, before captain Johan Botha hit the winning runs.
Herschelle Gibbs and Jacques Kallis added 96 for the second wicket in quick time after the Proteas lost Hashim Amla early. Gibbs slammed 10 fours and a six in his 54-ball assault in which he scored 64, before Mitchell Johnson ended his stay.
South Africa, cruising at the stage began to stumble and lost three wickets in the process. AB de Villiers, JP Duminy and Kallis fell in quick succession as the visitors slipped to 163-5 with Neil McKenzie and Mark Boucher left with the task to stem the rot.
Earlier, the South African bowlers pegged back Australia with quick wickets to reduce the hosts to 269 all out off 49.1 overs after captain Ricky Ponting won the toss and elected to bat.
After winning the toss and electing to bat first, the hosts’ young opening pair of David Warner and Shaun Marsh gave their team a confident start with a century stand before departing in quick succession.
Than Michael Hussey was run out while regaining the crease for 12 while skipper Ricky Ponting was caught by Gibbs of skipper Botha for 29.
Warner played a super innings of 69 off just 60 balls hitting six fours and two sixes before getting out.
He and Marsh added 114 runs for the opening wicket off 18.5 overs. Marsh scored a patient 43 off 63 balls and held one end up before he fell to Botha.
Australia: Shaun Marsh, David Warner, Ricky Ponting (capt), Mike Hussey, David Hussey, Brad Haddin, James Hopes, Mitchell Johnson, Nathan Hauritz, Nathan Bracken, Shaun Tait.
South Africa: Herschelle Gibbs, Hashim Amla, Jaques Kallis, AB de Villiers, Jean-Paul Duminy, Neil McKenzie, Mark Boucher, Johan Botha (captain), Albie Morkel, Dale Steyn, Makhaya Ntini.