The 25-year-old Rossouw, whose early limited-overs appearances for the Proteas in recent weeks have not been without teething problems and seen some ill-luck compound that, cut loose in a big way at revamped Adelaide Oval to deservedly earn the player-of-the-match mantle for his booming 78 off 50 balls.
It helped South Africa to a comfortable seven-wicket victory in the first of three T20 matches against Australia.
But Rossouw was a tad lucky when he was dropped on 7 by Australian debutant Nathan Reardon.
"I prayed and asked 'please drop it, miss it please' and luckily it happened. It's that sort of luck that you need in cricket," Rossouw told Netwerk24.
The second T20 between Australia and South Africa is played at the Melbourne Cricket Ground on Friday, while the third and final match of the series takes place at Stadium Australia in Sydney on Sunday.
Both games start from 10:35 (SA time).