The 25-year-old endured an unusually difficult first half of the campaign by her lofty standards.
She reached the Australian Open quarter-finals before losing to eventual champion Elena Rybakina, fell in the fourth round at Roland Garros, where she had previously excelled, and exited Wimbledon in the third round as she failed to defend her title.
Swiatek, who has slipped to eighth in the world rankings, captured her first title of the season earlier this month with a commanding victory over Rybakina in the Canadian Open final, providing a timely confidence boost ahead of the year's final Grand Slam.
After winning her maiden major title at Roland Garros in 2020, Swiatek has lifted at least one Grand Slam trophy in every season since 2022 and will be eager to preserve that streak.
"For me, for sure, it wasn't an easy season," Swiatek said on Saturday. "Probably the toughest one and the most challenging.
"Obviously, I had to change coaches before the clay-court season, which was a tricky situation. Then I started working with Francis (Francisco Roig), and just wanted to implement all the stuff that we did in practice.
"But, on the other hand, I didn't have a lot of practice time. So probably it calmed down; everything calmed down after Wimbledon. I managed to get some days off, reset a little bit, and we had a much longer training block.
"So it really helped me to just implement this stuff that I was talking about."
Swiatek said recent results had left her encouraged by the progress she has made.
"The last two tournaments (Canadian Open and Cincinnati Open) were super positive," she said.
"Even though I lost in Cincinnati, this match against Jess (Jessica Pegula in the semi-finals) was really high level.
"So I feel happy with my game and with the changes that I made. Just looking forward now."
The former world number one can also draw confidence from her record in New York, where she claimed the US Open title in 2022. She has not advanced beyond the quarter-finals at Flushing Meadows since, however, exiting at that stage in each of the last two years.
Swiatek opens her US Open campaign against China's Wang Xiyu.
The men's and women's singles main draws get under way later on Sunday.
US Open 2026
The US Open is the fourth and final Grand Slam of the tennis season, running from August 30th to September 13th. It is a hard-court tournament held at Flushing Meadows in New York City. Follow the links below for more information!
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