PARIS, France - Former doubles World No.1 Barbora Krejcikova's breakthrough Grand Slam in singles continued in Paris on Friday as the Czech rallied from a set down to beat Tsvetana Pironkova and reach the fourth round of the French Open, 5-7, 6-4, 6-3.

Despite having a total of four Grand Slam titles to her name between women's and mixed doubles, Krejcikova had only previously played two Grand Slam main draws in singles prior to earning direct entry this year in Paris with 15 losses in the qualifying rounds of majors dating back to 2014.

Her first Grand Slam main-draw win came earlier this year at the Australian Open, where she successfully qualified in a sixth trip to Melbourne Park, and she's now in the midst of a career-best major in a fourth singles trip to Paris.

After losing the opening set despite having an early break lead, the 24-year-old earned a hard-fought victory on Court 7 in two hours and 38 minutes, never losing serve across the second and third sets. 

The Czech secured the decisive breaks of serve near the start of each set, protecting her delivery well in the face of adversity. After saving a break point to lead 3-1 in the second set, she faced just one other - holding serve in a lengthy, four-deuce game to build an identical lead in the final set. 

Evenly matched from the baseline, both players racked up 36 winners over the course of the match and were nearly even with that total in unforced errors, as the Bulgarian totaled 39 and the Czech 38. 

"I think it was a really tough match, really difficult match, really up and down. I lost the first set. The conditions were really, really difficult," Krejcikova told reporters after the victory.

"I was just enjoying being out there, enjoying playing. First time third round of a Grand Slam. I was fighting for every ball, trying to do my best to win the match. At the end, I got very lucky and I won. I'm very, very happy."

In a poignant moment, the Czech secured her third-round victory on what would've been WTA Legend Jana Novotna's 52nd birthday. Krejcikova was coached and mentored by the Wimbledon champion and fellow Brno native earlier in her career in a partnership that began in 2014, before Novota's passing in 2017 from cancer.

"It was very emotional for me, very special that I could win this match today," Krejcikova said. "I would like to also dedicate it to her because she would be really happy for my result."

About Novotna, the 24-year-old continued: "It actually made it really, really tough. Really tough. I spoke with one of my friends, one of the former tennis players, she knew Jana well. We were talking about it a little bit. She's like, 'Okay, now is the time. You should play for her."

"I'm like, 'No, I cannot do this because I'm just going to get too emotional, and it's not going to help me.' I'm going to be more nervous, more tight and everything.

"I was like, 'No, I'm just going to go there, try to enjoy the match, and I see what's going to happen.' If I'm going to lose, still she's going to be really happy and really proud, so... I went like this for the match."

In a section of opportunity after the second-round loss of No.10 seed Victoria Azarenka and withdrawal of No.6 seed Serena Williams, the current World No.117 will next face Argentinian qualifier Nadia Podoroska, ranked World No.131, for a spot in a Grand Slam quarterfinal.

"I know she was playing the same tournaments as I did, so many ITFs. She was playing the WTA in Prague where I saw her. Until now I didn't know who I'm playing. I'm going to look at it tomorrow because tomorrow I have a doubles so I'm going to look at it after," the Czech said.

"I'm really proud of myself that I was finally able to step out and to show how I can play, that I can have a success also in singles, not only in doubles. I hope it's a right time to do it. I'm just enjoying it. I'm really happy to play a Grand Slam. It's always an extra motivation. It gives me an extra energy.

"It's very special. I'm just very happy that finally it just clicked in."

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