CINCINNATI, OH, USA - Andrea Hlavackova and Lucie Hradecka continued their excellent summer form on Thursday with a win over No.2 seeds Sara Errani and Roberta Vinci at the Western & Southern Open.

Meeting just six weeks after facing each other in the Wimbledon quarterfinals, it was Hlavackova and Hradecka who once again held their nerves when it mattered, playing a near-perfect match tie-break to edge out the Italians.

Hlavackova and Hradecka's reward for this 63 36 103 win is a meeting with the tournament's surprise package, Darija Jurak and Katalin Marosi.

Beneficiaries of Maria Kirilenko and Nadia Petrova's 11th hour withdrawal, alternates Jurak and Marosi advanced to their first Premier-level semifinal with a comeback victory over Varvara Lepchenko and Sloane Stephens, rallying from a set and 5-4 down before prevailing, 46 75 108.

On the other side of the draw, No.6 seeds Nuria Llagostera Vives and María José Martínez Sánchez enjoyed a far easier time of things, defeating Natalie Grandin and Vladimira Uhlirova, 61 62.

Meeting them in the semifinal will be the winner of the match between No.8 seeds Katarina Srebotnik and Zheng Jie and Eleni Daniilidou and Peng Shuai, the latter of whom knocked out top seeds Liezel Huber and Lisa Raymond, 64 64.