TASHKENT, Uzbekistan - The Tashkent Open has never had a repeat champion in its 19-year history, and it will have to wait another year for its first one as all three former champions left - Kristyna Pliskova, Nao Hibino and Pauline Parmentier - crashed out in the second round.

Read more: Defending champion Pliskova battles past Hsieh in Tashkent

Defending champion and top seed Pliskova held three set points on Kurumi Nara’s serve in the opening set, but the unseeded Japanese player battled through to a 7-6(5), 6-1 victory.

"I had lost to her last year here at Tashkent and so went into the match with a plan,” Nara told Tashkent Open’s Sunder Iyer. “I knew her game, and returned well in the match.

“She played better midway in the match but I did well to hold her. I'm very happy with my win, also it's my first quarterfinal of the year."

Kateryna Bondarenko (Tashkent Open)

In the quarterfinals she’ll take on Kateryna Bondarenko, who knocked out 2015 champion and last year’s finalist Hibino in tight straight sets, 6-4, 7-5.

"I was happy to finish the match in two sets as I was getting tired,” Bondarenko said. “I started making more errors and Nao started playing aggressively.

“I told myself that I had to win in two sets, the third set would have been a difficult situation. So I started playing better and stayed calm and finished the match.”

And former World No.2 Vera Zvonareva took down the last former Tashkent Open champion left in the draw when she defeated 2007 champion Pauline Parmentier in a comprehensive 6-2, 6-0 victory. Zvonareva will take on No.6 seed Aleksandra Krunic in the quarterfinals after the Serb weathered a mid-match wobble on her way to a 6-2, 1-6, 6-3 victory over Jana Cepelova.

Aleksandra Krunic at the Tashkent Open. (Tashkent Open)

With 2012 champion Irina-Camelia Begu also falling in the opening round, the event will once again have a new champion for the 19th year in a row - continuing the “Tashkent Open jinx”.

Also through to the quarterfinals, No.2 seed Timea Babos needed just over an hour to wrap up a comfortable victory over Denisa Allertova, 6-3, 6-3. She’s set to face Stefanie Voegele, who marked a triumphant return from her six-month injury layoff to knock out No.5 seed Marketa Vondrousova in a nearly three-hour battle, 7-6(8), 4-6, 7-5. Kateryna Kozlova moved past No.8 seed Ekaterina Alexandrova 6-2, 6-3, and Aryna Sabalenka defeated No.3 seed Tatjana Maria 6-3, 7-5, to claim the last two quarterfinal spots.