ABU DHABI, U.A.E. -- 18-year-old Marta Kostyuk says she has moved on from the pressure and expectation-filled last three years of her career and her results at the first event of the season, where she has advanced to her first WTA semifinal at the Abu Dhabi WTA Women's Tennis Open.

As a 15-year-old qualifier, the Ukrainian prodigy made her debut on the world stage with a run to the third round of the 2018 Australian Open. After receiving a wildcard into qualifying as the 2017 girls champion, Kostyuk tallied her first WTA main draw win in the first round over 25th seed Peng Shuai and became the youngest player to reach the third round in Melbourne since Martina Hingis in 1996. 

The expectations for the youngster immediately skyrocketed and, as she has openly discussed, were crippling. It took Kostyuk time to deal with the fallout of injuries and a stalled ranking, but after turning 18-years-old last June, Kostyuk says everything changed. 

"That was a really tough time in my life. I was really at my lowest. I had to go through depression, never talked about it."

"I used to have that pressure because there were a lot of girls who achieved big things before me," Kostyuk told reporters after her dominating 6-1, 6-1 win over Tamara Zidansek in the Round of 16 in Abu Dhabi. "Like Amanda [Anisimova] doing semifinals at Roland Garros, Iga [Swiatek] winning a Slam a few months ago, there were a lot of girls doing an amazing job the last few years. 

READ: 2018 Flashback - Getting to Know Marta Kostyuk

"I had a lot of pressure before I turned 18, that the moment I turn 18 no one would count me as anyone anymore. So basically if I turned 18 and I didn't accomplish anything, that means I'm really bad and I'm done. Like whatever I do in my career doesn't count anymore."

"The moment I turned 18, I kind of let all the things go. Right now, I don't have that pressure at all because I enjoy the journey, I enjoy the process, I enjoy being out here playing even though we have tough times because of COVID. 

"So no, I'm not really thinking about that pressure for now."

WTA Insider spoke to Kostyuk in Abu Dhabi about the long and difficult road to her Top 100 debut, what it took to finally banish the ghosts of the 2018 Australian Open from her psyche, and why she's ready to make an impact in 2021. 

Marta Kostyuk Abu Dhabi JJ

Marta Kostyuk serves during her first round match at the 2021 Abu Dhabi WTA Women's Tennis Open.

WTA/Jimmie48

WTA Insider: How did it feel to make finally make your Top 100 debut at the end of the year?
Kostyuk: That was my goal. Not at the beginning of the year, but when I arrived at the US Open we set the goal that I have to finish Top 100 because I want to be main draw at the Slams. It would give me a lot of benefits and confidence and that's what I'm playing for.

I'm just happy to finish in the Top 100. Now I'm not thinking about the rankings anymore and that I have to qualify somewhere and play qualifying for Slams. Qualifying for Slams is a tough thing. There are no easy matches. Now in Dubai (Australian Open qualifying) there are so many former Top 50, Top 30 players. It's tough. You have to be high level to pass the qualies. 

I'm happy I'm not in qualies. I'm happy to be here in Abu Dhabi.

"I want to finish Top 50 and I believe it can be even better than Top 50. My mom has higher goals but we're sticking to Top 50."

WTA Insider: What is your coaching set-up these days?
Kostyuk: My mom is my coach for my whole life. She used to play herself. 

With my mom, it's very tricky. She knows me best. I love working with her. We obviously have fights, sometimes less, sometimes more. We have a big emotional connection. We're mom and daughter. It's not common on tour to see a mom and daughter. It's tough because sometimes I want mom to only be the mom.

I have Riccardo Piatti helping me out. He's not my full-time coach because he's with Jannik [Sinner]. But I come there, I did my pre-season at his center, I was with him before my US swing. He mentors me, he coaches me when I come to see him. Tennis-wise it's a mix of mom and Riccardo.

WTA Insider: What are your goals for 2021?
Kostyuk: I want to finish Top 50 and I believe it can be even better than Top 50. My mom has higher goals but we're sticking to Top 50 (laughs). 

I think Top 50 is super real and it will not give me as much pressure as setting higher goals. I really want to go step-by-step. 

I don't want to rush and I don't want to put a lot of pressure on myself like three years ago when I did third round at the Australian Open. I couldn't cope with it. It was just too much of everything. 

So I think Top 50 is super real and I believe I'm going to achieve this goal by the end of the year.

Marta Kostyuk Abu Dhabi JJ

WTA/Jimmie48

WTA Insider: Do you think you've been able to close the book on that 2018 Australian Open run?
Kostyuk: That was a really tough time in my life. I was really at my lowest. I had to go through depression, never talked about it. I really tried to be super low-key at that time when I was struggling. 

That time in my life was super challenging. It was many things outside of the court. I was just falling apart. 

I would stick to that Australian Open for so long in my life. It was the highlight of my career back that. It was such a big deal and I just couldn't let that go, 'I want to go back to that feeling of how I was hitting the ball at that 2018 Australian Open.' 

It took me some time and strength to let that thing go. I compare it to the US Open last year when I made the third round, it wasn't such a big deal. Like, I just made third round, whatever, we keep on going. I'm just trying to not take winning as such a big deal. 

"I sat on the sofa next to the practice desk area and I was sitting there and I clearly remember saying, 'Oh my god, how am I going to defend these points next year?'"

It took me a lot of time to not want to rush, to take time, to understand what's really important. It was tough. Now I'm glad I went through it all, but it's just an experience. I don't want to take it as anything else. But it was tough.

Fun fact: The moment I played my third-round match against Elina Svitolina. I sat on the sofa next to the practice desk area and I was sitting there and I clearly remember saying, 'Oh my god, how am I going to defend these points next year?' I was living that whole 2018 year how I'm going to defend these points. There were a lot of reasons I thought that. 

Why I feel so much more relieved now is because I turned 18 last June and I can play as many tournaments as I want now. I don't have that border in my mind that oh, I only have two tournaments left, I have to plan my year.

WTA Insider: You're into your first quarterfinal at a WTA 500 event with three strong wins. What have you learned about the state of your game this week and how does this set you up for the season?
Kostyuk: I had this problem before, thinking I'm playing well, better than a lot of girls, but I could never understand what is my advantage. For example, Pliskova has an amazing serve, Coco runs very well and has a very good serve. There's a lot of players that have their own advantages. 

I was looking at myself and was like, serve is good, return is good, I can approach the net, there are many things I can do. But I cannot understand what is my "card" that I can always win with, win tough matches with.

During this week I saw some things that I do much better than the other girls. I can definitely see now my advantages a bit better. And I can use it for myself. I know exactly what I can do with the ball, where I can put it, how I can put it. 

I believe that on this knowledge that I got from this week and from the wins that I got, I feel like I can build much more in the upcoming year and this will give me a lot of advantage.

2021 Abu Dhabi Highlights: Svitolina outlasts Alexandrova