Istanbul, Turkey (SportsNetwork.com) - Italy's Roberta Vinci was among the second-round winners Thursday at the Istanbul Cup.
The second-seeded Vinci had opened a 6-3, 4-1 lead over Alexandra Dulgheru when the Romanian qualifier retired.
Vinci has now reached the quarterfinals in each of her last two events after a string of four straight first-round losses, which included early exits at both Wimbledon and the French Open. She lost to Simona Halep last week in the final at the Bucharest Open.
Next up for the nine-time WTA Tour winner will be Japan's Kurumi Nara. The sixth seed advanced Thursday with a 7-6 (7-5), 6-7 (3-7), 6-2 win over Czech qualifier Katerina Siniakova.
Eighth-seeded Karolina Pliskova also moved into the quarters with a 6-2, 7-5 win over Israel's Shahar Peer, the 2006 Istanbul champ. Pliskova earned a quarterfinal matchup with top-seeded Caroline Wozniacki. The Dane won her second-round match on Wednesday.
Croatian qualifier Ana Konjuh won a second straight three-set match, taking out Japan's Misaki Doi, 6-4, 6-7 (3-7), 6-4, and will next meet fourth-seeded Elina Svitolina of the Ukraine. Svitolina also advanced Wednesday.
Friday's remaining quarterfinal will feature Francesca Schiavone against Kristina Mladenovic.