The reigning Wimbledon champion, Ashleigh Barty won 11 of 14 games after dropping the first set. she was then broken twice while serving for the match and eventually dropped a shocker to American Shelby Rogers 6-2, 1-6, 7-6 (7/5).
"It's never nice when you have a couple of opportunities to serve out a match and can't get it done," Barty said. "Six in the third is brutal, It's a tough one to swallow.
"I found a way to really turn it in my favour and just wasn't able to just quite finish off. It's disappointing but we'll move on."
The 25-year-old Australian fell one round shy of matching her deepest US Open run. It's the only slam where she hasn't reached the semifinals.
"I feel like the slams you're kind of building up to it and afterwards there's a reset," Barty said. "We reset now. We go back to the drawing board, work out what we want to do for the rest of the season."
Barty won titles this year at Miami, Melbourne, Stuttgart and Cincinnati as well as her second Grand Slam crown despite being away from her homeland since February.
"The last six months have been a roller coaster," Barty said. "I'm proud of myself and my team for all the efforts we've put in. It has been pretty incredible. I don't think we could have asked for much more honestly. I wouldn't change a thing.
"With all of the tough moments we've had, it has created some of the most enjoyable experiences. I've learned so much about myself, about them, the way that we work together. It's been truly an incredible six months."
One of her great experiences was playing her first night match in Arthur Ashe Stadium, even in a loss.
"It was an awesome experience to play on Ashe at night. It's an incredible atmosphere," she said. "Absolutely incredible. They gave me energy. It seemed pretty chockers to me, seemed pretty full. It was a lot of fun out there."
Barty said she took some positives from the match but won't linger on the loss.
"There's a lot that's disappointing, but a lot that's positive," she said. "Not a match I'll dwell on for too long in the sense that there are so many 'what ifs.' Millimetres could have changed things.
"You accept that in tennis. That's the way the cookie crumbles sometimes and you move on it from it pretty quick.
"I just didn't quite have enough physically or mentally in the tank. But that's OK... I sleep well tonight knowing I gave everything I could. It just wasn't quite enough.
"We're looking forward to celebrating the good stuff we've done, learning from the hurt, learning from the experiences, and moving on."