NEW YORK, NY, USA - The bright lights of Manhattan have done little to rattle Dayana Yastremska's sharp focus at the 2019 US Open. 

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"I like New York," the No.32 seed said after her first round win over Monica Niculescu. "It’s really nice, and an energetic city, but I’m not the one who would like to live here. It’s too much; people are rushing all the time, you don’t really feel your space, and everyone is crazy here!"

At just 19 years old - and a year removed from her Grand Slam main draw debut - Yastremska is into the third round in only her second appearance at the USTA Billie Jean King National Tennis Center, and will play fellow Odessa native and No.5 seed Elina Svitolina in an all-Ukrainian battle for the second week.

"It's good," said Svitolina, "because one of the Ukrainians going to be in the fourth round."

For Yastremska, the encounter has been in the works for a while.

"We’ve had many opportunities to play in the past but I think I was the one losing the match before!" she laughed after defeating Rebecca Peterson in a postponed second round clash. " I think it will be a very interesting match because we’re a bit of different style. It’ll be nice for the fans, especially the Ukrainian fans. They’ll be so excited to see this match."

So focused was the teenager that she spun around on match point against Peterson, not realizing she had won.

"I saw the score and didn’t realize it was match point for me, but rather, advantage for her," she explained in her typically breathless tone. "I was like, ‘What’s going on?’ But I had decided to go to net no matter what, so I was just like, ‘Already? It’s done?’"

It had indeed appeared to be an audacious way to end the match for the aggressive baseliner, crashing the net to win what she at least considered to be a key point.

"It wasn’t something special but it was the first time I’d won a match without realizing it! I think I was just very focused on each ball, and forgot a little bit."

The first woman born in the new millennium to crack the Top 100, Yastremska, who is coached both by her parents - "my father is like my tennis coach, and my mother is more like my mental coach!" - and Olivier Jeunehomme, has been on the move since last fall when she won her first title at the Prudential Hong Kong Tennis Open. Two more titles to start 2019 in Hua Hin and Strasbourg - not to mention a trip to the second week of Wimbledon - have not only proven her potential on all surfaces, but also helped her nab a seed in Flushing Meadows. 

Trending towards a big result all summer, she earned wins over Victoria Azarenka and Caroline Wozniacki at the Rogers Cup and Western & Southern Open, respectively.

"Everything is simple," she chirps. "You focusing on where you’re playing, and just practice."

In what has been a tournament about teenagers - led by No.15 seed Bianca Andreescu and 15-year-old American Coco Gauff - Yastremska very much fits that mold, laughingly checking her phone to double check the day on which she arrived in New York, but the behavior belies a fierce competitor. 

Dialing down her light-hearted demeanor down to a whisper, she determined her best would appear in time for the final major tournament of the decade.

"I made it a goal to play really well here, so no matter my preparation or how I was playing in Toronto or Cincinnati, I knew I would get my focus back here. I just believe I can do well."

Yastremska incurred knee and foot injuries at the end of her Cincinnati match against eventual finalist and 2004 US Open champion Svetlana Kuznetsova - a match she served for and held two match points. Restricting her practice schedule, she took advantage of the chance to unwind with friends like Katarina Zavatska and 2017 French Open champion Jelena Ostapenko, visiting the King's Island amusement park with the latter.

"She’s a very nice girl, a very cool person, who is very funny and crazy. We’ve been friends for so long. I always thought she was more of an aggressive girl, but once I got to know her, she’s completely different outside tennis.

"When you’re on tour, you’re always so focused and practicing, it’s important to have a friend you can hang out with and have fun."

Rested and healthy, the Ukrainian will play her countrywoman on Louis Armstrong Stadium - focused on making the most of her first appearance under the spotlight, one she has been working towards since her junior days.

"When I was young..."

She pauses and smiles.

"Well, I’m still young, but when I was playing junior tournaments, I also played on big stages. I always liked playing in front of the public, and having people support you. Sometimes you’re on a big stage and they’re cheering for you and other times for your opponent. You don’t really hear either because you’re completely blocking that out, and are just...in your own way on the court.

"I don’t really mind the stage I’m on, but I prefer the big ones."