We said it at the beginning! At least one Aussie woman was going to make a US Open final, but it sure wasn't going to be in singles.
The general consensus is if Sabalenka can mature in her decision-making, Belarus will have discovered their next Azarenka before the progenitor is even finished. An interesting dynamic between the two, to say the least.
Together they have overpowered a relatively easy draw to make it to this stage, easily accounting for a string of opponents that, while honestly you'd expect them to beat, have proven giant-killers in their own right.
But here's where it gets really interesting.
Women's doubles is increasingly random in the draws it throws out and this final is the perfect example of that. The growing versatility among women's tennis players at the elite level lends itself to eradicating the doubles specialist. Crossovers are now queen.
As if to illustrate the point, Barty was arguably one of the few pure doubles champions in the world and she just won the French Open singles.
Meanwhile, the most dedicated doubles partnership in the US Open draw, China's Duan Yingying and Zheng Saisai were trounced in straight sets by 'Mertelenka' (now it's just getting offensive) in the quarters.
Like Barty and Azarenka, Sabalenka and Mertens evidence this shift across tennis. They've forged a decent doubles career together and made the quarter-finals at Wimbledon, but have also had to forego tournaments due to their singles commitments.
Yet their combination of resolute power and individual skill has won out. They don't compliment each other as fluently as Barty and Azarenka, but they almost don't need to.
Whoever you support (c'mon Barty) and whatever happens in their final Monday morning AEST, it will certainly be an intiguing watch; a blueprint for the evolution of the women's game.
Oh, and it's just going to bloody excellent tennis. Did we mention hard-hitting?