BUCHAREST, Romania - Unseeded Kazakh Elena Rybakina bounced the highest seed remaining from the BRD Bucharest Open in Friday's quarterfinals.

The 20-year-old rallied from a 5-3 first set deficit, and saved two set points, en route to beating No.2 seed Viktoria Kuzmova, 7-6(4), 6-3.

After saving two break points in the first game of the match, Rybakina dropped serve to trail 2-1, the Kazakh won just two points in Kuzmova's next three service games, and was two points away from losing the opener. 

However, from 30-30 on her serve in the eighth game, she held on, and proceeded to break Kuzmova on her first break point chance of the set after saving both set points.

"I started not so good, and didn't serve like yesterday - yesterday I served really well," Rybakina said. 

"I started a bit slower and I wasn't mving so well, but I just tried to focus each point. I lost only one service game, and I just tried to focus and that's why I think I won this match."

In the second set, Rybakina again broke serve at her first opportunity to lead 3-2 and battled through a pair of tough holds en route to holding on for the match. 

The World No.106 saved four break points against her in a six-deuce sixth game, and later saved another break point opportunity in the eighth before breaking the World No.54 for the fourth time in the match to seal victory.

Rybakina scored her second career win against Kuzmova with the upset, and advanced to her second semifinal of the year as as a result.

The rising Kazakh came through qualifying at the Libéma Open and fell to World No.4 Kiki Bertens in the final four on grass, and will face either Barbora Krejcikova or Martina Di Giuseppe for a spot in her first final.

"Of course, I want to play in the finals - winning the tournament would be perfect," Rybakina said with a laugh.

"I've already played one semifinal on WTA so I'm just focusing on the next match."