SHENZHEN, China — Defending champion Katerina Siniakova defeated Maria Sharapova 6-2, 3-6, 6-3 on Friday in her first meeting with the five-time major winner to reach the final of the Shenzhen Open.

The sixth-seeded Siniakova hit 10 aces to set up a final on Saturday with top-ranked Simona Halep, who beat fourth-seeded Irina-Camelia Begu 6-1, 6-4.

"I'm so happy," Siniakova said. "You could see the emotions after I finally won the last point. It was a tough match for me, and even tougher to close it."

Sharapova, who is set for a return to the Australian Open which starts on Jan. 15, struggled with her serve, double faulting five times. Sharapova missed last year's tournament during a doping ban that dated back to a failed test for meldonium at Melbourne Park in 2016.

In the first semifinal in Shenzhen on Friday, Halep had 15 winners and four service breaks as she maintained her perfect record against her doubles partner, improving to 6-0 against Begu.

"It was a tough match, I know that she's a very strong player and in the second set, you could see that she was improving her game," Halep said. "I was strong enough to hit the ball (well) in the end."