The Socceroos had beaten New Zealand 1-0 in Brisbane on Thursday and triumphed again at Eden Park despite fielding an entirely different starting XI, netting twice in the second half.

New Zealand was the better side in the first half with a handful of half chances, but lost star striker Chris Wood to an apparent rib injury in the 32nd minute.

Australia's Marco Tilio missed a golden opportunity on the stroke of half-time before Mitchell Duke headed in Connor Metcalfe's cross in the 54th minute to open the scoring.

The host had a sniff in the 68th minute when Harrison Delbridge turned over possession in a dangerous area but substitute Alexander Greive fired straight at Australia goalkeeper Andrew Redmayne.

Exciting Socceroos teenager Garang Kuol made his debut as a substitute and burst forward to set up Riley McGree's chance, which was saved before Cummings' rebound was handballed by Liberato Cacace, resulting in a penalty for Australia.

Scotland-born Cummings stepped up and converted the 81st-minute penalty to secure the win in Australia's final game before announcing its World Cup squad.