SHENZHEN, China (AP) — On a day of upsets at the Shenzhen Open, Kristyna Pliskova beat defending champion Aryna Sabalenka 6-4, 6-4 and Anna Blinkova defeated top-seeded Belinda Bencic 3-6, 6-3, 6-3 on Tuesday.
Pliskova had 15 aces and saved 11 break points against Sabalenka.
"She's playing so fast, so I had to be ready from the first point. My serve was there, which is always important, so I'm happy that I won," Pliskova said. "I'm happy because I reached the quarterfinals here two years ago, so I'm happy to be back there and looking to see if I can do more."
Pliskova will next play Kateryna Bondarenko after she defeated eighth-seeded Shuai Zhang 7-6 (8), 6-3 in the second round.
Blinkova rallied to beat Bencic in her opening-round match, serving a dozen aces and breaking her opponent's serve five times.
"It was a great performance from me today," Blinkova said. "I prepared very carefully and I'm happy that I played good tennis. I was thinking to just fight for every point."
The 21-year-old Blinkova lost five of the first six games but recovered well.
"I didn't feel great in the beginning of the match," Blinkova said. “I didn't play bad, but I managed to increase the level of my game slowly, step by step.
"I said to myself that I needed to put more balls in the court, because I was giving her too many mistakes. I tried to play big margins, but aggressive."
The Russian will next face Zarina Diyas in the second round. Diyas defeated wild-card entry Yingying Duan 6-3, 6-4.
Elise Mertens also reached the quarterfinals, beating Xiyu Wang 6-4, 6-3.