Gauff fulfilled what had long seemed her destiny by winning in New York, as she came from a set down to beat Sabalenka.
This time she was unable to repeat the feat as Sabalenka ended her unbeaten start to the 2024 season.
Gauff arrived in Melbourne after winning a WTA title in Auckland and didn't drop a set in her first four matches.
But after beating Ukraine's Marta Kostyuk in what she considered a “bad” quarter-final, she appeared extremely nervous in the early stages of the semi-final.
Gauff's tension was evident in six double faults in the first set, although she also showed her ability to mentally reinvent herself when she twice recovered from collapses.
After soaking up so much pressure, Gauff got to 6-5 but missed the chance to serve the set at 30-0 and was penalized when Sabalenka dominated the tiebreak.
Gauff had to fend off further break points in the first and sixth games of the second set, with the pressure becoming clear when Sabalenka made mistakes from the baseline to break 5-4.
This time Sabalenka didn't miss the opportunity and earned the “revenge” she wanted to exact on Gauff for her defeat in Flushing Meadows.
“It was a tough game for me,” said Gauff, who was close to tears as she left Rod Laver Arena.
“Overall it was a positive tournament. I had chances in both sets, but she played better. I think it just came down to a few points, and that’s tennis.”