The former world number one beat 11th seed Petra Kvitova in straight sets, 7-5, 7-6(4) on Wednesday in what was her first victory over a top-20 player in nearly five years.
Wozniacki has been away from competitive tennis for over three years before returning To work less than a month ago.
The Danish star gave birth to two children during her break, but has always remained close to the sport, taking part in legendary doubles events and working as a TV analyst.
In June of this year, she announced her intention to return and hasn’t looked back since.
She made light work of her first round match at Flushing Meadows and was in great form again against two-time Grand Slam champion Kvitova.
After the win, Wozniacki was seen sitting in her chair and wiping away tears of joy as the fantasy race continued in New York.
“Obviously I knew before the match that I had a chance to win, and I believe in myself. At the same time, it’s clear she’s had a great year,” Wozniacki said after the match. Professional Tennis Players Association.
“She’s an 11-year-old in the world, and she loves to play on hard courts. I knew it was going to be a very tough game and I had to play my best.
She later told reporters: “I am so happy to have the opportunity to play on Arthur Ashe Court. Three years ago, if you ask me, I never thought I would play on one of those courts again at the US Open, especially in night training.
“It’s an incredible feeling to be there and win a game like that.”
Wozniacki won 30 singles titles, including the 2018 Australian Open, before initially retiring in 2020.
Her last victory over a top 20 player was against Kvitova again in 2018.
Wozniacki, 33, who was the US Open runner-up in 2009 and 2014, will face American Jennifer Brady in the next round.
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