SHENZHEN (AFP) - Unseeded Czech tennis player Katerina Siniakova defeated Britain's world No. 10 Johanna Konta on Friday to secure a place in the WTA Shenzhen Open final.

She eliminated second seed Simona Halep earlier in the US$750,000 (S$1.1 million) tournament but another upset looked unlikely when Konta raced into a 5-0 first-set lead and took it minutes later.

But the world No. 52 recovered to level the match. Third seed Konta again took the lead in the decider, but Siniakova won the last four games to triumph 1-6, 6-4, 6-4.

"I think she definitely started slower in the match, and me, quite well," Konta said. "But all credit to her, she really raised her level in the next two sets.

"She was going for every single shot and played quite freely, so it was a difficult match for me to do what I would have liked."

In the final, Siniakova will face American Alison Riske, whose winning streak in China continued as she defeated Italy's Camila Giorgi in straight sets, 6-3, 6-3.

The 26-year-old is ranked 39th in the world and has now only ever reached five WTA Tour finals - four of them in China, including Shenzhen last year and the 2014 Tianjin Open, which remains her only tour victory.