SEOUL -- When Frances Tiafoe's rousing run at the US Open came to an end in the semifinals earlier this month, he received a text message from his childhood friend, Hailey Baptiste. 

"I texted him after his semifinal match, 'Tough one, good week,'" Baptiste told WTA Insider. 

"He didn't say anything about the match. He just said, 'You can do it too.'" 

Seoul: Scores | Order of Play | Draw

Baptiste, 21, is four years Tiafoe's junior and grew up alongside him and his family in Washington D.C. In a month of "See it, to be it" stories, led by Taylor Townsend and Donald Young's mixed doubles reunion in New York, Baptiste echoed similar sentiments when it came to her childhood friend.

"He's always a huge inspiration to me and he's like a brother to me," Baptiste said. "We went to school together and when I was in fourth grade I'd be with him all day and hang out with him every weekend, and we're still close to this day. Same with his brother, his parents, they're basically my family. 

"To see that, of course it's possible because I've grown up with him and he's right there."

Baptiste is ranked No.105 on the PIF WTA Rankings this week at the Hana Bank Korea Open. She scored a confidence-boosting win in the first round, defeating Sloane Stephens 7-6(4), 6-2 and will face top seed Daria Kasatkina in the Round of 16 on Thursday. A win would be her first Top 20 win in over five years and move her into her first Hologic WTA Tour quarterfinal. 

While other players might be flagging this late in the season, Baptiste finds herself rejuvenated. She credits a bit part of that to her new coach, Alex Bogomolov, Jr. The former ATP player, who hit a career-high No.33 in 2011, has helped Baptiste bring structure and fun to her training, something she admits was lacking for much of the year. 

"I've had so many matches where I've been super close," Baptiste said, "and maybe if I won those matches, maybe I would have gone on a run. That's tennis though, the difference between one forehand, one point. 

"I think in those moments, confidence is huge. Not having a coach and everything, not being able to train, that was a big part of not getting through those moments. I was having a lot of doubt. I knew that I needed the structure and I was frustrated. Then I'd get in those [tight] moments and I would feel the doubts and I would get more frustrated. That was definitely a big thing that was playing in my head."

"I knew I needed somebody, it was just a matter of who. So many coaches live in Europe."

- Hailey Baptiste

Baptiste linked up with Bogomolov on the court, but it wasn't a tennis court. A chance meeting over a year ago in Florida sowed the seeds of their collaboration. Baptiste was hanging out with her good friend Whitney Osuigwe and her brother, who wanted to hit the public basketball courts. 

"He was playing basketball and there was this guy sliding around playing defense, and I was like, for sure this guy was a tennis player," Baptiste said. "It turned out to be him. That was a year and a half ago. When I split with my coach this year I messaged him because he lives close to me and we started working together."

The challenge for Baptiste and Bogomolov is to tune her aggressive all-court game to stand up to the match-up challenges she faces. Armed with a heavy forehand that takes time to set up, the American has found herself unsettled against flat-hitting opposition. 

"Using my serve, slice, coming in, being aggressive on my forehand, that's me," Baptiste said. "I try to stay true to that, which is difficult sometimes because I hit a heavier ball and so when I'm playing people who are playing people who play super flat, which is a lot of people on the WTA, it's obviously difficult to play with that heavy ball."

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Experience has helped Baptiste figure out solutions, but there's a tactical and technical side to the equation as well. 

"I still sometimes struggle with it a little bit, but I definitely starting to feel more comfortable," she said. "I think the slice helps a lot because it forces them to lift the ball a little bit and then I can crank the heavy ball and start playing the way I want to.

"I think it's hand speed and staying low because I naturally don't have a super low stance. I have to remind myself to get a little lower just to be able to hit a clean ball when that shooting flat ball is coming at me."

This week in Seoul, Baptiste will is flying solo. Bogomolov will join her next week at the China Open in Beijing. But with a few wins over the coming weeks, Baptiste could find herself eclipsing her career-high ranking of No.96 before the season ends. 

"Not mad at the year that I've had," Baptiste said, "but this pre-season I'm looking to push and clean up some things and have a better season next year."