Top seed Simona Halep of Romania returns to Serbian Aleksandra Krunic during their quarterfinal match at the Shenzhen Open tennis tournament on Thursday in Shenzhen, South China’s Guangdong Province. After winning 6-3, 6-3, Halep will play Chinese player Zheng Saisai in the semifinals on Friday. Photo: CFP

 
Top seed and world No.3 ­Simona Halep, along with ­second seed Petra Kvitova, ranked four, both breezed past lowly opponents in straight sets on Thursday to reach the semifinals of the Shenzhen Open.

Romanian Halep, last year's French Open runner-up, made short work of Serbian qualifier Aleksandra Krunic, winning through 6-3, 6-3 in 62 minutes.

Double Wimbledon winner Kvitova needed slightly longer to dispose of her fellow Czech Tereza Smitkova but did so 7-5, 6-4.

Kvitova will play Swiss No.8 seed Timea Bacsinszky in the semifinals, after former world No.2 Vera Zvonareva's injury devils returned to haunt her and she retired in tears just 29 minutes into her first WTA quarterfinal since 2012.

The Russian reached the Wimbledon and US Open ­finals in 2010 but has since been plagued by injury and illness, dropping to No.250 in the world, and was attempting to launch a 2015 comeback at the $500,000 tournament.

Zvonareva was already 3-2 down after 47th-ranked Bacsinszky, her doubles partner, broke her serve.

Halep's semifinal opponent will be home player Zheng ­Saisai, 20, who is ranked 97th but beat fourth seed Zarina ­Diyas of Kazakhstan 3-6, 7-6 (7/2), 6-2 to maintain Chinese interest in the event.