ISTANBUL, Turkey - Defending champion Cagla Buyukakcay returned to the quarterfinals of the TEB BNP Paribas Istanbul Cup on Thursday with an upset of No.2 seed Timea Babos, 6-4, 7-6(5).
On the top half of the draw, top seed Elina Svitolina was largely untroubled in a 6-3, 6-3 win over qualifier Alexandra Cadantu to book her place in the last eight.
Buyukakcay, who hadn't won a tour-level main draw match since the 2016 US Open before this week, scored just her second career win against a top 30 player.
Buyukakcay and Babos, who are also still alive as a doubles pair in Istanbul, played a tight match from first ball over nearly two hours. The defending champion dug out of a 0-40 hole at 1-1 in the first set and used her momentum to break in the next game, before saving a pair of break points to wrap up the opener, 6-4.
Though Buyukakacay secured a love break in the first game of the second set, Babos hit back in the fifth game to draw the second set even, and the two remained on serve until the Turkish No.2 secured her second break in the 11th game to serve for the match.
Babos made her last stand from there, breaking serve to send the set to a tiebreak, but was unable to wrestle a lead after the first point of the tiebreak as Buyukakacay wrapped up the match in straight sets.
In the top half of the draw, No.1 seed and World No.13 Svitolina booked her place in her first quarterfinal since winning the Dubai Duty Free Tennis Championships in February.
"I'm feeling a bit better, I needed some time to get used to this court," Svitolina said. "I was expecting the girls who played through the qualifiers, yesterday and today, they got used to it. I needed to stay strong, and I think I did this pretty good [today]."
Though Svitolina dropped serve once in each set against her Romanian opponent, she responded with a total of five breaks of serve to secure her second win in three career meetings against Cadantu.
"I'm looking forward to the quarterfinal," Svitolina said of her next opponent, No.5 seed Sorana Cirstea. "I had a couple of days here, and I think I'm good. We all know her, and she's playing good, and I will try to bring my game and fight for every ball."