The Socceroos had been dealt the blow of losing first-choice striker Tomi Juric to injury and some supporters were critical of Nabbout's selection in the initial squad ahead of Hibernian's Jamie Maclaren, but the Urawa Reds man repaid Bert van Marwijk's faith as Australia cruised in Austria.
It took the Socceroos a little while to get going at the NV Arena in St. Polten, but they finally came to life upon taking the lead 32 minutes in – Leckie tucking in from close range.
From then on, Australia looked considerably more dangerous in attack than their European counterparts, who showed little to suggest their World Cup qualification failure was a fluke.
Nabbout made it 2-0 early in the second half, providing a fierce finish a few moments before being withdrawn, with his mission seemingly accomplished.
Leckie got his second 18 minutes from time, before a late Jakub Jugas own goal saw Australia clinch a victory which suggests they are in good shape with just one more preparation game scheduled before facing France in Kazan in their World Cup opener on June 16.
