Top seed Caroline Wozniacki and 16-year-old Croatian qualifier Ana Konjuh reached the Istanbul WTA semi-finals on Friday.

Konjuh defeated Elina Svitolina 6-4 1-6 6-1 to become the youngest player to reach a WTA semi-final since a 16-year-old Donna Vekic made the Tashkent final in 2012.

Awaiting Konjuh is second seed Roberta Vinci, who enjoyed a 6-0 6-2 win over sixth seed Kurumi Nara in just 49 minutes.

Wozniacki rallied past eighth seed Karolina Pliskova 6-1 3-6 6-2 while France’s Kristina Mladenovic won a two-hour, 23-minute marathon against former French Open winner Francesca Schiavone, 3-6 6-3 7-5.

“I’m happy with the way I’ve been serving this week and it definitely helped me out there today,” Wozniacki said.

“Karolina is a tough opponent and she always gives me a lot of trouble. I knew it was not going to be easy.”