A dejected Talia Gibson is doing her best to extract the positives after Donna Vekic crashed the rising star's US Open party in a rough start for the Australian contingent.
Storm Hunter and Adam Walton also made early exits on day one at Flushing Meadows as Gibson was unable to disguise her anguish at an opportunity lost.
The 22-year-old rallied from a set and a service break down to look poised to claim her maiden grand slam victory outside Australia before Vekic steadied to post a 6-2, 4-6, 6-3 in two hours and 33 minutes.
The veteran Croat and 2024 Wimbledon semifinalist seemed to be unravelling after blowing a set and 4-1 lead, cursing herself and berating her box as Gibson roared back into the contest.
But Gibson was unable to wrestle back control after failing to convert any of four break-point chances in the second game of the deciding set.
She had Vekic down 0-40 serving at 4-2, only to miss five straight returns to ruefully let the Paris Olympics silver medallist off the hook.
"It's a hard one to swallow," Gibson said.
"Most of the time it's who makes the most unforced errors on the court who comes away with the loss and today that was me, so it's just something to learn from."
But after starting the year well outside the world's top 100, Gibson has slashed her ranking in half after racking up some 30 match wins, including over former No.1 and dual Australian and US Open champion Naomi Osaka.
"Days like these are really tough. It's hard not to be disappointed. When it comes to the slams, every player wants to do well," said the world No.63.
"But if I'm looking at my entire year so far, I've been able to achieve some things that probably at the start of the year I probably wouldn't have thought I'd be able to do.
So to still be in the position ranking that I currently have and moving forward to these next tournaments, I don't really have any points to defend, so it's kind of just no pressure and more opportunities."
Aussie qualifier Storm Hunter was defeated by 11th seed Marta Kostyuk in straight sets.
After stumbling at this year's Australian Open, Kostyuk has been in sublime form at the grand slams, making the semifinals of the French Open and Wimbledon to arrive at Flushing Meadows as a genuine contender in the women's draw.
The 11th seed got down to business quickly once the match began and powered to a 4-1 lead before overcoming a wobble to close out the first set when Hunter produced a double fault on set point.
Kostyuk tightened her grip on the clash in the second set, breaking early and never allowing Hunter a route back into the match as she wrapped up a 6-4, 6-1 victory in 67 minutes.
"I'm very happy to be back to this amazing place," Kostyuk said on court.
"It's not easy to play a qualifier, they've played a whole tournament [already]. I'm very happy with my performance today. I try to keep myself grounded. There's still a long way to go, I'm enjoying my tennis."
Adam Walton also bowed out early, missing two set points in the third set of a tight 7-6 (7-2), 6-2, 7-5 loss to China's Yibing Wu.
Aleksandar Vukic, up against Japan's Rei Sakamoto, is the only other Australian in men's action.
Kim Birrell faces Petra Marcinko and rising star Taylah Preston takes on American Alycia Parks.
World number seven and three-time US Open quarterfinalist Alex de Minaur opens his title quest on Tuesday against Italian qualifier Andrea Guerrieri.
